**IMISCOE Research Series**

# Peter Scholten *Editor*

# Introduction to Migration Studies

An Interactive Guide to the Literatures on Migration and Diversity

IMISCOE Research Series

Now accepted for Scopus! Content available on the Scopus site in spring 2021.

This series is the official book series of IMISCOE, the largest network of excellence on migration and diversity in the world. It comprises publications which present empirical and theoretical research on different aspects of international migration. The authors are all specialists, and the publications a rich source of information for researchers and others involved in international migration studies. The series is published under the editorial supervision of the IMISCOE Editorial Committee which includes leading scholars from all over Europe. The series, which contains more than eighty titles already, is internationally peer reviewed which ensures that the book published in this series continue to present excellent academic standards and scholarly quality. Most of the books are available open access.

More information about this series at https://link.springer.com/bookseries/13502

Peter Scholten Editor

# Introduction to Migration Studies

An Interactive Guide to the Literatures on Migration and Diversity

Editor Peter Scholten Erasmus School of Social and Behavioural Sciences; Room T17-16 Erasmus University Rotterdam, Zuid-Holland, The Netherlands

ISSN 2364-4087 ISSN 2364-4095 (electronic) IMISCOE Research Series ISBN 978-3-030-92376-1 ISBN 978-3-030-92377-8 (eBook) https://doi.org/10.1007/978-3-030-92377-8

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### Migration Research Hub Connection Team

### Contents

#### Part I Introduction to Migration Studies

#### Contents ix

#### Part VI Methods in Migration Studies

Raffaella Greco Tonegutti, and Claudio Paravati

### Part I Introduction to Migration Studies

### Chapter 1 An Introduction to Migration Studies: The Rise and Coming of Age of a Research Field

Peter Scholten, Asya Pisarevskaya, and Nathan Levy

Migration studies has contributed significantly to our understanding of mobilities and migration-related diversities. It has developed a distinct body of knowledge on why people migrate, how migration takes place, and what the consequences are of migration in a broad sense, both for migrants themselves and for societies involved in migration. As a broadly-based research field, migration studies has evolved at the crossroads of a variety of disciplines. This includes disciplines such as sociology, political science, anthropology, geography, law and economics, but increasingly it expands to a broader pool of disciplines also including health studies, development studies, governance studies and many more, building on insights from these disciplines.

Migration is itself in no way a new phenomenon; but the specific and interdisciplinary study of migration is relatively recent. Although the genesis of migration studies goes back to studies in the early twentieth century, it was only by the end of the twentieth and the beginning of the twenty-first century that the number of specialised master programmes in migration studies increased, that the number of journal outlets grew significantly, that numerous specialised research groups and institutes emerged all over the world, and that in broader academia migration studies was recognised as a distinct research field in its own right. By 2018 there were at least 45 specialised journals in migration studies (Pisarevskaya et al., 2019, p. 462). The field has developed its own international research networks, such as IMISCOE (International Migration, Integration and Social Cohesion in Europe), NOMRA (Network of Migration Research on Africa), and the global more policy-oriented network Metropolis. Students at an increasingly broad range of universities can

P. Scholten (\*)

Erasmus School of Social and Behavioural Sciences; Room T17-16, Erasmus University, Rotterdam, Zuid-Holland, The Netherlands e-mail<EMAIL_ADDRESS>
A. Pisarevskaya · N. Levy

Erasmus School of Social and Behavioural Sciences, Erasmus University Rotterdam, Rotterdam, Netherlands

study dedicated programs as well as courses on migration studies. Slowly but gradually the field is also globalising beyond its European and North American roots.

Migration studies is a research field, which means that it is not a discipline in itself with a core body of knowledge that applies to various topics, but an area of studies that focus on a specific topic while building on insights from across various disciplines. It has clear roots in particular in economics, geography, anthropology and sociology. However, when looking at migration publications and conferences today, the disciplinary diversity of the field has increased significantly, for instancing bringing important contributions from and to political sciences, law, demography, cultural studies, languages, history, health studies and many more. It is hard to imagine a discipline to which migration studies is not relevant; for instance, even for engineering studies, migration has become a topic of importance when focusing on the role that social media play as migration infrastructures. Beyond being multidisciplinary (combining insights from various disciplines), the field has become increasing interdisciplinary (with its own approach that combines aspects from various disciplines) or even transdisciplinary (with an approach that systematically integrates knowledge and methods from various disciplines).

#### 1.1 A Pluralist Perspective on Migration Studies

Migration studies is a broad and diverse research field that covers many different topics, ranging from the economics of migration to studies of race and ethnicity. As with many research fields, the boundaries of the field cannot be demarcated very clearly. However, this diversity does also involve a fair degree of fragmentation in the field. For instance, the field features numerous sub-fields of study, such as refugee studies, multicultural studies, race studies, diversity studies, etc. In fact, there are many networks and conferences within the field with a specific focus, for instance, on migration and development. So, the field of migration studies also encompasses, in itself, a broad range of subfields.

This diversity is not only reflected in the topics covered by migration studies, but also in theoretical and methodological approaches. It is an inherently pluralistic field, bringing often fundamentally different theoretical perspectives on key topics such as the root causes of integration. It brings very different methods, for instance ranging from ethnographic fieldwork with specific migrant communities to large-n quantitative analyses of the relation between economics and migration.

Therefore, this book is an effort to capture and reflect on this pluralistic character of field. It resists the temptation to bring together a 'state of the art' of knowledge on topics, raising the illusion that there is perhaps a high degree of knowledge consensus. Rather, we aim to bring to the foreground the key theoretical and methodological discussions within the field, and let the reader appreciate the diversity and richness of the field.

However, the book will also discuss how this pluralism can complicate discussions within the field based on very basic concepts. Migration studies stands out from most other research fields in terms of a relatively high degree of contestation of some of its most basic concepts. Examples include terms as 'integration', 'multiculturalism', 'cohesion' but perhaps most pertinent also the basic concept of 'migration.' Many of the field's basic concepts can be defined as essentially contested concepts. Without presuming to bring these conceptual discussions to a close, this book does bring an effort to map and understand these discussions, aiming to prevent conceptual divides from leading to fragmentation in the field.

This conceptual contestation reflects broader points on how the field has evolved. Various studies have shown that the field's development in various countries and at various moments has been spurred by a policy context in which migration was problematised. Many governments revealed a clear interest in research that could help governments control migration and promote the 'integration' of migrants into their nation-states (DeWind, 2000). The field's strong policy relevance also led to a powerful dynamic of coproduction in specific concepts such as 'integration' or 'migrant.' At the same time, there is also clear critical self-reflection in the field on such developments, and on how to promote more systematic theory building in migration studies. This increase of reflexivity can be taken as a sign of the coming of age of migration studies as a self-critical and self-conscious research field.

An introduction to migration studies will need to combine a systematic approach to mapping the field with a strong historical awareness of how the field has developed and how specific topics, concepts and methods have emerged. Therefore, in this chapter, we will do just that. We will start with a historical analysis of how the field emerged and evolved, in an effort to show how the field became so diverse and what may have been critical junctures in the development of the field. Subsequently, we will try to define what is migration studies, by a systematic approach towards mapping the pluralism of the field without losing grip of what keeps together the field of migration studies. Therefore, rather than providing one sharp definition of migration studies, we will map that parts that together are considered to constitute migration studies. Finally, we will map the current state of the research field.

To provide a comprehensive overview of such a pluralist and complex field of study, we employ a variety of methods. Qualitative historical analysis of key works that shaped the formation and development of the field over the years is combined with novel bibliometric methods to give a birds-eye view of the structure of the field in terms of volume of publications, internationalisation and epistemic communities of scholarship on migration. The bibliometric analysis presented in this chapter is based on our previous articles, in which we either, used Scopus data from 40 key journals (Pisarevskaya et al., 2019, or a complex key-word query to harvest metadata of relevant publications from Web of Science (Levy et al., 2020). Both these approaches to meta-data collection were created and reviewed with the help of multiple experts of migration studies. You can consult the original publications for more details. Our meta-data contained information on authors, years of publication, journals, titles, and abstracts of articles and books, as well as reference lists, i.e. works that were cited by each document in the dataset.

In this chapter you will see the findings from these analyses, revealing the growth trends of migration specific journals, and yearly numbers of articles published on migration-related topics, number and geographical distribution of international co-authorships, as well as referencing patterns of books and articles – the "cocitation analysis". The colourful network graphs you will see later in the chapter, reveal links between scholars, whose writings are mentioned together in one reference list. When authors are often mentioned together in the publications of other scientists, it means that their ideas are part of a common conversation. The works of the most-cited authors in different parts of the co-citation networks give us an understanding of which topics they specialise in, which methods they use in their research, and also within which disciplinary traditions they work. All in all, co-citation analysis provides an insight on the conceptual development of epistemic communities with their distinct paradigms, methods and thematic foci.

In addition, we bring in some findings from the Migration Research Hub, which hosts an unprecedented number of articles, book chapters, reports, dissertation relevant to the field. All these items are brought together with the help of IT technologies, integration with different databases such as Dimensions, ORCID, Crossref, and Web of Science, as well as submitted by the authors themselves. At the end of 2020, this database contains around 90,000 of items categorised into the taxonomy of migration studies, which will be presented below.

#### 1.2 What Is Migration Studies?

The historical development of migration studies, as described in the next section, reveals the plurality of the research field. Various efforts to come up with a definition of the field therefore also reflect this plurality. For instance, King (2012) speaks of migration studies as encompassing 'all types of international and internal migration, migrants, and migration-related diversities'. This builds on Cohen's (1996, p. xi–xii) nine conceptual 'dyads' in the field. Many of these have since been problematised – answering Cohen's own call for critical and systematic considerations – but they nonetheless provide a skeletal overview of the field as it is broadly understood and unfolded in this book and in the taxonomy on which it is based:

Therefore, the taxonomy provides the topical structure—elaborated below—by which we approach this book. We do not aim to provide a be-all and end-all definition of migration studies but rather seek to capture its inherent plurality by

bringing together chapters which provide a state-of-the-art of different meta-topics within the field.

The taxonomy of migration studies was developed as part of a broader research project, led by IMISCOE, from 2018 to 2020 aimed at comprehensively taking stock of and providing an index for the field (see the Migration Research Hub on www. migrationresearch.com). It was a community endeavour, involving contributors from multiple methodological, disciplinary, and geographical backgrounds at several stages from beginning to end.

It was built through a combination of two methods. First, the taxonomy is based on a large-scale computer-based inductive analysis of a vast number—over 23,000—of journal articles, chapters, and books from the field of migration studies. This led to an empirical clustering of topics addressed within the dataset, as identified empirically in terms of keywords that tend to go together within specific publications.

Secondly, this empirical clustering was combined with a deductive approach with the aim of giving logical structure to the inductively developed topics. Engaging, at this stage, with several migration scholars with specific expertise facilitated a theorydriven expansion of the taxonomy towards what it is today, with its hierarchical categorisation not only of topics and sub-categories of topics, but also of methods, disciplines, and geographical focuses (see Fig. 1.1 below).

In terms of its content, the taxonomy that has been developed distinguishes various meta-topics within migration studies. These include:

Fig. 1.1 The structure of the taxonomy of migration studies

All the topics in the taxonomy are grouped into several branches: Migration processes, Migration Consequences, Migration governance and Cross-cutting. In Fig. 1.2 below you can see how many journal articles, books, book chapters and reports can be found in the migration research hub just for the period of the last 20 years. The number of items belonging to each theme can vary significantly, because some of them are broader than others. Broader themes can be related to larger numbers of items, for instance 'migration forms' is very broad, because it includes many types and forms of migration on which scientific research in this field chooses to focus on. On the contrary, the theme of 'governance processes' is narrower because less studies are concerned with specific processes of migration management, such as criminalisation, externalisation or implementation.

The various chapters in this book can of course never fully represent the full scope of the field. Therefore, the chapters will include various interactive links with the broader literature. This literature is made accessible via the Migration Research Hub, which aims to represent the full scope of migration studies. The Hub is based on the taxonomy and provides a full overview of relevant literature (articles, chapters, books, reports, policy briefs) per taxonomy item. This not only includes works published in migration journals or migration books, but also a broader range of publications, such as disciplinary journals.

Because the Hub is being constantly updated, the taxonomy—along with how we approach the question of 'what is migration studies?' in this book—is interactive; it is not dogmatic, but reflexive. As theory develops, new topics and nomenclature emerge. In fact, several topics have been added and some topics have been renamed since "Taxonomy 1.0" was launched in 2018. In this way, the taxonomy is not a fixed entity, but constantly evolving, as a reflection of the field itself.

Fig. 1.2 Distribution of taxonomy branches in the Migration Research Hub

#### 1.3 The Historical Development of Migration Studies

#### 1.3.1 An Historical Perspective on "Migration Studies"

A pluralist perspective on an evolving research field, therefore, cannot rely on one single definition of what constitutes that research field. Instead, a historical perspective can shed light on how "migration studies" has developed. Therefore, we use this introductory chapter to outline the genesis and emergence of what is nowadays considered to be the field of migration studies. This historical perspective will also rely on various earlier efforts to map the development of the field, which have often had a significant influence on what came to be considered "migration studies".

#### 1.3.2 Genesis of Migration Studies

Migration studies is often recognised as having originated in the work of geographer Ernst Ravenstein in the 1880s, and his 11 Laws of Migration (1885). These laws were the first effort towards theorising why (internal) migration takes place and what different dynamics of mobility look like, related, for instance, to what happens to the sending context after migrants leave, or differing tendencies between men and women to migrate. Ravenstein's work provided the foundation for early, primarily economic, approaches to the study of migration, or, more specifically, internal or domestic migration (see Greenwood & Hunt, 2003; Massey et al., 1998).

The study of international migration and migrants can perhaps be traced back to Znaniecki and Thomas' (1927) work on Polish migration to Europe and America. Along with Ravenstein's Laws, most scholars consider these volumes to mark the genesis of migration studies.

#### The Polish Peasant and the Chicago School

The Polish Peasant in Europe and America—written by Florian Znaniecki & William Thomas, and first published between 1918 and 1920—contains an in-depth analysis of the lives of Polish migrant families. Poles formed the biggest immigrant group in America at this time. Thomas and Znaniecki's work was not only seminal for migration research, but for the wider discipline of sociology. Indeed, their colleagues in the Department of Sociology at the University of Chicago, such as Robert Park, had a profound impact on the discipline with their groundbreaking empirical studies of race and ethnic relations (Bulmer, 1986; Bommes & Morawska, 2005).

Greenwood and Hunt (2003) provide a helpful overview of the early decades of migration research, albeit through a primarily economic disciplinary lens, with particular focus on America and the UK. According to them, migration research "took off" in the 1930s, catalysed by two societal forces—urbanisation and the Great Depression—and the increased diversity those forces generated. To illustrate this point, they cite the bibliographies collated by Dorothy Thomas (1938) which listed nearly 200 publications (119 from the USA and UK, 72 from Germany), many of which focused on migration in relation to those two societal forces, in what was already regarded as a "broadly based field of study" (Greenwood & Hunt, 2003, p. 4).

Prior to Thomas' bibliography, early indications of the institutionalisation of migration research came in the US, with the establishment of the Social Science Research Council's Committee on Scientific Aspects of Human Migration (see DeWind, 2000). This led to the publication of Thornthwaite's overview of Internal Migration in the United States (1934) and one of the first efforts to study migration policymaking, Goodrich et al's Migration and Economic Opportunity (1936).

In the case of the UK in the 1930s, Greenwood and Hunt observe an emphasis on establishing formal causal models, inspired by Ravenstein's Laws. The work of Makower et al. (1938, 1939, 1940), which, like Goodrich, focused on the relationship of migration and unemployment, is highlighted by Greenwood and Hunt as seminal in this regard. The New Palgrave Dictionary of Economics regards Makower and Marschak as having made a "pioneering contribution" to our understanding of labour mobility (see also the several taxonomy topics dealing with labour).

#### 1.3.3 The Establishment of a Plural Field of Migration Studies (1950s–1980s)

Migration research began to formalise and expand in the 1950s and 1960s (Greenwood & Hunt, 2003; Pedraza-Bailey, 1990). A noteworthy turning point for the field was the debate around assimilation which gathered pace throughout the 1950s and is perhaps most notably exemplified by Gordon's (1964) typology of this concept.

#### Gordon's Assimilation Typology and the Problematisation of Integration

Assimilation, integration, acculturation, and the question of how migrants adapt and are incorporated into a host society (and vice versa), has long been a prominent topic in migration studies.

Gordon (1964) argued that assimilation was composed of seven aspects of identification with the host society: cultural, structural, martial, identificational, behavioural, attitudinal, and civic. His research marked the beginning of hundreds of publications on this question of how migrants and host societies adapt. The broader discussions with which Gordon interacted evolved into one of the major debates in migration studies.

By the 1990s, understandings of assimilation evolved in several ways. Some argued that process was context- or group-dependent (see Shibutani & Kwan, 1965; Alba & Nee, 1997). Others recognised that there was not merely one type nor indeed one direction of integration (Berry, 1997).

The concept itself has been increasingly problematised since the turn of the century. One prominent example of this is Favell (2003). Favell's main argument was that integration as a normative policy goal structured research on migration in Western Europe. Up until then, migration research had reproduced what he saw as nation-state-centred power structures. It is worth reading this alongside Wimmer and Glick Schiller (2003) to situate it in broader contemporary debates, but there is plenty more to read on this topic.

For more on literature around this topic, see Chaps. 19, 20, and 21 of this book.

Indeed, these debates and discussions were emblematic of wider shifts in approaches to the study of migration. The first of these was towards the study of international (as opposed to internal) migration in the light of post-War economic dynamics, which also established a split in approaches to migration research that has lasted several decades (see King & Skeldon, 2010). The second shift was towards the study of ethnic and race relations, which continued into the 1970s, and was induced by the civil rights movements of these decades (Pedraza-Bailey, 1990). These two shifts are reflected in the establishment of some of the earliest journals with a migration and diversity focus in the 1960s—the establishment of journals being an indicator of institutionalisation—as represented in Fig. 1.3. Among these are journals that continue to be prominent in the field, such as International Migration (1961-), International Migration Review (1964-), and, later, the Journal of Ethnic and Migration Studies (1970-) and Ethnic & Racial Studies (1978-).

By the 1970s, although several new journals of migration studies had emerged and the field was maturing in terms of theory-building, there remained a lack of interdisciplinary "synthesis" (Kritz et al., 1981; King, 2012). This is reflected in the research of Levy et al. (2020). Based on citation data showing who migration researchers cited over the years, Fig. 1.4 maps the embryo-like development of migration studies every half-decade from 1975 to the present day. In the early decades it shows distinct "epistemic communities" (represented by colours) clustered together based on disciplines in migration research. For example, the earlier decades show economists focused on development (sky blue); economic sociologists analysing the labour market behaviour of migrants (royal blue); demographers (green); and sociologists studying the assimilation topic (red) mentioned above. By the late 1980s, a new cluster of social psychologists (yellow) emerged, with a combination of demographers and economists clustering (pink) in the 1990s. The figure shows an increasing coherence to the field since then, as the next section elaborates, but the 1970s and 1980s was a period of disciplinary differentiation within migration studies.

Although the field may not have been interdisciplinary in the 1980s, it was indeed multidisciplinary, and research was being conducted in more and more countries:

Fig. 1.3 Number of journals focused on migration and migration-related diversity (1959–2018). (Source: Pisarevskaya et al., 2019, p. 462) (R&C Race & Class, IM International Migration, IMR International Migration Review, SE Studi Emigrazione, PP Patterns of Prejudice, JBS Journal of Black Studies, JEMS Journal of Ethnic and Migration Studies, PDR Population and Development Review, IJIR International Journal of Intercultural Relations, ERS Ethnic & Racial Studies, JIS Journal of Intercultural Studies, RSQ Refugee Survey Quarterly, REMI Revue Européenne des Migrations Internationales, MW Migration World, JRS Journal of Refugee Studies, LCC Language, Culture, and Curriculum, APMJ Asian and Pacific Migration Journal, HM Hommes et Migrations, Id. Identities, PSP Population, Space, and Place, CDEMP Cultural Diversity and Ethnic Minority Psychology, IMIS IMIS-Beitrage, EH Ethnicity & Health, CS Citizenship Studies, JSIE Journal of Studies in International Education, REE Race, Ethnicity, and Education, EJML European Journal of Migration and Law, JIMI Journal of International Migration and Integration, NJMR Norwegian Journal of Migration Research, Ethn. Ethnicities, GN Global Networks, JIRS Journal of Immigrant & Refugee Studies, ML Migration Letters, ZAA Zeitschrift für Ausländerrecht und Ausländerpolitik, IJMHSC International Journal of Migration, Health, and Social Care, LS Latino Studies, FJEM Finnish Journal of Ethnicity and Migration, Mob. Mobilities, JDHE Journal of Diversity in Higher Education, NJMR Nordic Journal of Migration Research (merger of NJMR and FJEM), IZAJM IZA Journal of Migration, CEEMR Central and Eastern European Migration Review, MS Migration Studies, CMS Comparative Migration Studies, Mov. Movements, JMH Journal of Migration History, M&S Migration & Society. For more journals publishing in migration studies, see migrationresearch.com)

This period entailed a "veritable boom" of contributions to migration research from several disciplines, according to Pedraza-Bailey (1990), along with a degree of internationalisation, in terms of European scholarship "catching up" with hitherto dominant North American publications, according to Bommes & Morawska, (2005). English-language migration research was still, however, dominated by institutes based in the global North and the 'West'.

Fig. 1.4 Co-citation clusters of authors cited in migration studies literature 1975–2018. (From Levy et al., 2020, p. 18)

#### Interdisciplinarity and Internationalisation in Migration Studies: Key Readings

There have been several publications dealing with the development of migration studies over the years. These readings identify some of the key points related to interdisciplinarity in the field, and how the field has evolved internationally.

#### Brettell, C. B., & Hollifield, J. F. (2000). Migration theory: Talking across disciplines (1st ed.). Abingdon: Routledge; 2nd ed. (2008); 3rd ed. (2015).

Talking Across Disciplines has been used as a standard textbook in migration studies for several years. It represents the first effort towards highlighting the key ideas of the multiple disciplines in the field. It offers an introduction to the contributions these disciplines, as well as critical reflections on how those disciplines have interacted.

(continued)

#### Bommes, M., & Morawska, E. (2005). International migration research: Constructions, omissions and the promises of Interdisciplinarity. Farnham: Ashgate.

International Migration Research is one of the first attempts to explore and synthesise migration studies from an interdisciplinary perspective. In this book, scholars from multiple disciplines provide a state of the art of the field which illuminates the contrasts between how these disciplines approach migration studies. It is one of the first works in which migration studies is understood to be an institutionalised field of study.

#### Thränhardt, D., & Bommes, M. (2010). National Paradigms of migration research. Osnabrück: V&R.

In this book, readers are introduced to the idea that migration studies developed as a policy-driven field in several countries in the twentieth century. Not only did this entail diverse policy priorities, but also diverse "paradigms" of knowledge production in terms of terminology, concepts, and measures. This diversity reflects different national science policies. There are chapters reflecting on these processes from multiple continents, and from both "old" and "new" immigration countries.

In the decades before the 1990s—with a heavy reliance on census and demographic data—quantitative research abounded in migration studies (Greenwood & Hunt, 2003). But by the beginning of the 1990s, a "qualitative turn", linked more broadly to the "cultural turn" in social sciences, had taken place (King, 2012). In other words, migration studies broadly shifted from migration per se, to migrants. King notes the example of geographical research: "human geography research on migration switched from quantitatively inclined population geography to qualitatively minded cultural geographers [...] this epistemological shift did not so much re-make theories of the causes of migration as enrich our understanding of the migrant experience" (King, 2012, p. 24). Indeed, this is also reflected in how Pedraza-Bailey (1990, p. 49) mapped migration research by the end of the 1980s into two main categories: (i) the migration process itself and (ii) the (subjective) processes that follow migration.

Even though it is clear that migration studies is made up of multiple communities—we have already made the case for its pluralist composition—it is worth re-emphasising this development through the changing shape and structure of the 'embryos' in Fig. 1.4 above. The positioning of the clusters relative to each other denotes the extent to which different epistemic communities cited the same research, while the roundness of the map denotes how the field can be considered an integrated whole. We clearly see that in the period 1975–1979, the disciplinary clusters were dispersed, with loose linkages between one another. In the 1980s through to the mid-1990s, while some interdisciplinarity was emerging, several clusters, such as demographers and psychologists, were working largely within their own disciplines. In other words, in the 1970s and 1980s, authors working on migration referred to and were cited by other scholars primarily within their own disciplinary traditions. In this time, although a few migration journals had been established, this number was small compared to today. Without many scientific journals specialised in their topic, migration scholars were largely reading and publishing in disciplinary journals. By today—particularly in Europe—this has changed, as the increasing roundness of the maps demonstrate and as the rest of this chapter substantiates.

#### 1.3.4 Expansion of Migration Studies Since the Turn of the Century

In the 2000s the expansion of migration studies accelerated further (see Fig. 1.5). In 1975, there were just under 350 articles published on migration; there were 900 published in 2000; in 2017, over 3000 articles were published. This growth not only involved a diversification of the field, but also various critical conceptual developments and the rise of an increasingly self-critical approach to migration studies. One of these critical developments involved a move beyond a strong focus on the national dimension of migration and diversities, for example in terms of understanding migration as international migration, on integration as a phenomenon only within nation-states, and on migrants as either being connected to the 'home' or 'host' society.

Several key publications marked this important turn. Wimmer and Glick-Schiller (2002) refer to "methodological nationalism" and critique the notion of taking the nation-state as a given as if it were a natural entity. In fact, for Wimmer and Glick

Fig. 1.5 Number of articles, per year, in migration studies dataset based on advanced query of Web of Science for Migration Research Hub, 12 March 2019. (Based on Levy et al., 2020, p. 8)

Schiller, this way of understanding reality helps contribute to nation-state building more than it enhances scientific knowledge. In a similar contribution, Favell (2003) critiques the concept of 'integration' as naturalising the nation-state in relation to migration. Favell's main argument was that integration as a normative policy goal structured research on migration in Western Europe. Up until then, migration research had reproduced what he saw as nation-state-centred power structures. Thranhardt and Bommes (2010) further substantiate this point by showing empirically how migration studies developed within distinct national context leading to the reification of distinct national models of integration/migration.

Where did this turn beyond methodological nationalism lead to? Several important trends can be defined in the literature. One involves the rise of perspectives that go beyond nation-states, such as transnationalist (Faist 2000, Vertovec 2009) and postnationalist (Soysal & Soyland, 1994) perspectives. Such perspectives have helped reveal how migration and migrant communities can also be shaped in ways that reach beyond nation-states, such as in transnational communities that connect communities from across various countries or in the notion of universal personhood that defines the position of migrants regardless of the state where they are from or where they reside.

Another perspective takes migration studies rather to the local (regional, urban, or neighbourhood) level of migration and diversity. Zapata-Barrero et al. speak in this regard of the local turn in migration studies (2010). They show how migrationrelated diversities take shape in specific local settings, such as cities or even neighbourhoods, in ways that cannot be understood from the traditional notion of distinct national models.

Also, in the study of migration itself, an important trend can be identified since the 2000s. Rather than focusing on migration as a phenomenon where someone leaves one country to settle in another, the so-called "mobility turn" (Boswell & Geddes, 2010) calls for a better comprehension of the variation in mobility patterns. This includes for instance variation in temporalities of migration (temporary, permanent, circular), but also in the frequency of migration, types of migration, etc. In this book we will address such mobilities in the forms of different types of migration, frequencies and temporalities by discussing very different migration forms.

#### 1.3.5 Growing Self-Critical Reflection in Migration Studies

Since the 2000s, there has also been a growing reflexive and self-critical approach within migration studies. Studies like those of Wimmer and Glick-Schiller, Favell, and Dahinden are clear illustrations of this growing conceptual self-consciousness. The field of migration studies has itself become an object of critical reflection. In the context of this book, we take this as a signal of the coming of age of migration studies.

This critical reflection touches upon a variety of issues in the field. One is how the field has conceptualised ethnicity, which was criticised as "ethnic lensing" (Glick Schiller & Çağlar, 2009). This would involve an inherent tendency to connect and problematise a broad range of issues with ethnicity, such as studies on how ethnic communities do on the labour market or the role that ethnicity plays in policies. The core argument to move beyond ethnic lensing is that focusing only on ethnicity risks defying social complexity and the importance of intersectionalities between ethnicity and, for instance, class, citizenship, education, location, cultural, or political disposition, etc. Dahinden (2016) calls in this context for a "de-migrantisation" of migration studies to avoid the naturalisation of migrants in relation to all sorts of issues and problems. Vertovec (2007) develops the concept "super-diversity" in this context to capture the social complexity of migration-related diversities.

Another strand of critical reflection concerns the field's relationship to policymaking. Studies like those by Scholten et al. (2015) and Ruhs et al. (2019) offer critical reflection on the role that the relationship between migration studies and broader policy settings has played in the conceptual and methodological development of the field. On the one hand, the evolution of the field has been spurred on in its policy relevance, for instance in research on migration management or 'migrant integration'. This relationship has contributed to the co-production of knowledge and key concepts, such as 'integration', and impeded the critical and independent development of the field. On the other hand, the field also leaves important gaps in research-policy relations, leaving important areas of knowledge production hardly connected to knowledge utilisation. Such studies have raised awareness of the necessity of research-policy relations for the societal impact of the field, while also problematising the nature of research-policy relations and their impact on the development of the field itself.

Finally, also in the context of growing public awareness on racism, the field has increasingly become self-reflexive in terms of how it deals with issues of discrimination and racism. This includes a growing awareness of institutional racism in the field itself, such as in institutes or training programs. Besides contributing to the broader field, there has been an increase of instances where institutes revise their own management and procedures in order to enhance racial justice. This includes participation of scholars from the global south, but also a proliferation of diversity policies in the field. At the same time, criticism remains on the extent to which the field has acknowledged issues of racial justice, for instance in studies on integration, migration management, or social cohesion.

#### 1.4 Mapping Migration Studies Today

#### 1.4.1 Co-Citation Communities

Nowadays, migration studies has become a more interdisciplinary field. In the last 15 years, as the "embryo" development in Fig. 1.4 shows, it became more ovalshaped without sharp "tails". This form indicates a cross-disciplinary osmosis; a growing interlinkage of epistemic communities. Co-referencing of authors from

Fig. 1.6 Co-citation map of authors with 10+ citations in migration research in the period 2005–2014. (From Levy et al. 2020, p. 17)

different disciplinary orientations became more common in the twenty-first century. Such developments can be attributed, on one hand, to the rapid digitisation of libraries and journals, as well as the multiplication of migration-focused journals, which accepted relevant contributions to discussion on migration, no matter the discipline. On the other hand, interdisciplinary endeavours were encouraged externally, for instance via grants (see European Union, 2016) and interdisciplinary master programmes created in various universities. It became fashionable to work at the intersection of disciplines, to an extent that nowadays it is often difficult to determine the disciplinary origin of a publication about migration. Whether such developments have yielded any theoretical or empirical breakthroughs is yet to be seen. In any case, it is clear that migration studies moved from being a multidisciplinary field (with few connections between them) to an interdisciplinary field (with more connections between multiple disciplines) (Levy et al., 2020).

Let us now dive into the most recent co-citation clusters. Such clusters are, of course, not only categorised in terms of disciplines. They also have certain topical focuses. Figure 1.6 below zooms in to the data from Fig. 1.4 and shows the co-citation network in the period 2005–2014 in more detail. We can see seven different groups of migration scholarship that are nevertheless rather interlinked, as the oval shape of the network indicates. At 1 o'clock we can see the cluster we have elsewhere called the "Global systems school", which has developed around such scholars as Vertovec, Soysal, Levitt, Favell, Faist, and Glick-Schiller, who introduced and developed the concept of transnationalism since the late 1990s. Contrasting with longstanding conventions of looking at migration as having an 'endpoint' in the countries of reception, they developed a different view of migration as a global, on-going, and dynamic process impacting receiving as well as sending societies, along with the identities, belonging, and 'sense of home' of migrants themselves. Nowadays, this cluster includes a very diverse group of scholars with different thematic focuses, such as the migration-development nexus (see also Chap. 18, this volume) including de Haas, Carling, and Castles; prominent scholars on Asian migration, such as Ong and Yeoh; and many others, Guarnizo, King, Anderson, Sassen, Joppke and Baubock. Yet, the fact that they all belong to one cluster, proves that their work has been cited in the same reference lists, thus constituting an interlinked conversation on migration as global phenomenon.

Closer to the centre of the network, we find a blue cluster, centred around Portes, a widely-cited founding father of migration studies in the USA. Next to him we also see other leading American scholars such as Waldinger, Alba and Zhou, Waters, Rumbaut, and Putnam, whose primary concern is the (economic) integration of immigrants. This cluster of scholars has elsewhere been understood as the "Michigan-Wisconsin" school of migration research, given the two universities' success in training migration scholars in the US (cf. Hollifield, 2020). Traditionally this scholarship has developed in the USA and has been very prominent in the field for decades. Especially Portes is cited extensively, and widely co-cited across the epistemic communities of the whole field.

This cluster is closely interlinked with the neighbouring (at 4 o'clock) cluster of economists, demographers, and other quantitative social scientists (turquoise). At the centre of it is Massey, another giant of migration studies, who mainly conducted his migration research from a demographic perspective. Here we also see economists such as Borjas, Chiswick, and Stark, who predominantly studied the immigration reality of the USA.

Then, at 6 o'clock, we see a light-green cluster. The highly cited scholars in its core are Williams and Krieger, who study migration- and race-related differences in health. For instance, Williams' highly-cited paper is about the experiences of racism and mental health problems of African Americans, while Krieger investigated how racism and discrimination causes high-blood pressure. Health is one of the 'younger' topics in contemporary migration studies; the amount of research on the intersection of migration and health has increased significantly in the last decade (Pisarevskaya et al., 2019).

Closely interlinked with 'health' is the cluster of 'acculturationists', positioned at 7 o'clock. The cluster is formed around J.W. Berry, a social-psychologist who introduced a theory of immigrant acculturation (1997). Scholars in this cluster investigate cross-cultural and intercultural communication from the psychological perspective. Other prominent authors in this cluster include Phinney, Pettigrew, Ward and Tajfel who studied cognitive aspects of prejudice, and Stephan famous for their integrated threat theory of prejudice (Stephan & Stephan, 2000).

Another significant group of scholars is positioned between 9 and 12 o'clock of the co-citation network. These are scholars focused on the politics of ethnic and race relations; prominent critical sociologists such as Foucault and Bourdieu are frequently co-cited in this cluster. Among the key authors in this group are Hall, Gilroy, Brubaker, Kymlicka, Asante, Du Bois, and Bonilla-Silva.

At 12 o'clock, we can see an orange cluster, positioned between the ethnic/race relations cluster and the "Global systems school" – this is a relatively new cluster of scholars working on the topic of mobility, developed by Urry, Scheller, and T. Cresswell. Other researchers within this loosely connected cluster focus in their research on mobilities from related to work and studies from the perspective of social and economic geography. The focus on mobility has been on the rise; it entered top three most prominent topics in migration studies in the period 2008–2017 (Pisarevskaya et al., 2019).

Overall, in the twenty-first century, the scholarship of migration in its variety of approaches and intertwined themes has seemed to move away from "'who'- and 'what'- questions, to 'how'- and 'why'-questions", compared to the early days of this field. Efforts towards quantifying and tracing geographies of migration flows and describing migrant populations in the receiving countries have somewhat declined in academic publications, while research on the subjective experiences of migrants, perceptions of migrants' identity and belonging, as well as attention to the cultural (super)diversity of societies has become more prominent (ibid.).

#### 1.4.2 Internationalisation

Since migration is a global phenomenon, it is important that it is studied in different countries and regions, by scholars with different academic and personal backgrounds, as well as for knowledge to be transferred around the world. Only by bringing together the diversity of perspectives and contexts in which migration is studied we can achieve a truly global and nuanced understanding of migration, its causes, and its consequences.

Over the course of the field's development, migration studies has internationalised. Even though analysis of internationalisation trends has only been conducted on English-language literature, the trends seem to be rather coherent. The number of the countries producing publications on migration has increased from 47 to 104 in the past 20 years. Publications from non-Anglophone European countries have increased by 15%, to constitute by today almost a third of Englishlanguage publications on migration, while the relative share of developed Anglophone countries (USA, UK, Canada, Australia) has declined (Pisarevskaya et al., 2019). The proportion of migration research that is internationally co-authored has also increased over the past 20 years, from 5% of articles in 1998 to over 20% in 2018 (Levy et al., 2020).

Nevertheless, international collaboration is not equally spread across the world. European and North American migration scholars have produced the highest absolute number of international collaborations between 1998 and 2018, though the relative share of collaborations among Europe-based scholars is much higher (36%) than that of their North American colleagues (15%). The suggested reasons behind these trends could be that critiques of national paradigms in migration studies have been taken up in Europe more eagerly than in North America. This has not happened without facilitation by broader science policies, particularly in the European Union, which funded the creation of the IMISCOE Network of Excellence, a network which intensified international collaborations between the research institutes working on migration and integration issues in various European countries.

In the global south, similar initiatives have been established, such as the Network for Migration Research on Africa and the Asia Pacific Knowledge Network on Migration. In these regions, international co-authorships are not uncommon, but the absolute number of publications in English compared to those from the north is small. We have thus observed an "uneven internationalisation" of migration studies (Levy et al., 2020); in the case of the gender and migration nexus, for instance, Kofman (2020) argues that the concentration of institutions and publishers in migration studies headquartered in the north perpetuates such inequalities.

#### 1.5 An Outlook on This Interactive Guide to Migration Studies

This book is structured so as to provide an overview of key topics within the pluralist field of migration studies. It is not structured according to specific theories or disciplines, but along topics, such as why and how people migrate, what forms of migration are there, what the consequences of migration are, and how migration can be governed. Per topic, it brings an overview of key concepts and theories as well as illustrations of how these help to understand concrete empirical cases. After each chapter, the reader will have a first overview of the plurality of perspectives developed in migration studies on a specific theme as well as first grasp of empirical case studies.

The book is designed as an 'interactive guide'; it will help connect readers to readings, projects, and reports for the selected themes via interactive links. To this aim, the book outline largely follows the official taxonomy of migration studies at migrationresearch.com. Throughout the text, there will be interactive links to overview pages on the Migration Research Hub, as well as to specific key readings. This marks the book as a point of entry for readers to get to know the field of migration studies.

#### Bibliography

Alba, R., & Nee, V. (1997). Rethinking assimilation theory for a new era of immigration. International Migration Review, 31(4), 826–874.

Berry, J. W. (1997). Immigration, acculturation, and adaptation. Applied Psychology, 46(1), 5–34.

Peter Scholten is Full Professor of Governance of Migration and Diversity at Erasmus University. Also, he is director of IMISCOE, editor-in-chief of the journal Comparative Migration Studies, and director of the Leiden-Delft-Erasmus Research Center on the Governance of Migration and Diversity.

Asya Pisarevskaya is a postdoctoral researcher in the Department of Public Administration and Sociology at Erasmus University Rotterdam and was one of the managing coordinators of the H2020 project CrossMigration.

Nathan Levy is a PhD candidate in the Department of Public Administration and Sociology at Erasmus University Rotterdam and was part of the co-ordination team of the CrossMigration Horizon 2020 project.

Open Access This chapter is licensed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license and indicate if changes were made.

The images or other third party material in this chapter are included in the chapter's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the chapter's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder.

### Chapter 2 Migration Histories

Marlou Schrover

It is impossible to cover the history of global migrations in one chapter. Dirk Hoerder (2002) in his seminal work Cultures in Contact needed 800 pages to map global migrations in the past millennium (see also Bosma et al., 2013; Lucassen & Lucassen, 1997, 2009, 2010; Lucassen et al., 2014). The Encyclopedia of Global Human Migration takes five thick volumes to cover global migration since Antiquity (Ness et al., 2013). The literature on global migration has increased rapidly since the 1980s. This increase is more-or-less in line with the increase in publications on migration control and migration management. The number of publications about global migration history is much less (see Fig. 2.1).

This chapter will and cannot not cover the global migrations in the past 2000 years, but rather it will look critically at data collections, present biases in migration history, and will give a helicopter view of major migrations.

#### 2.1 Biases and What Is New?

It is easy to argue—and many people have—that the migration of today is different from that of the past. In politics, this is done to pitch the 'good' migrant of the past against the 'bad' migrant of today, or to problematise current migration (Lucassen & Lucassen, 2011; Winter, 2012). Furthermore, if migration and integration are not presented as new issues, it is not news and thus not worthy of a journalist's attention, nor is there need for new policies or government intervention.

There is a tendency to present the immigrants of the past as desired immigrants, while many of today's immigrants are presented as not. For instance, 1 million

M. Schrover (\*)

History Department, Leiden University, Leiden, The Netherlands e-mail<EMAIL_ADDRESS>
<sup>©</sup> The Author(s) 2022

P. Scholten (ed.), Introduction to Migration Studies, IMISCOE Research Series, https://doi.org/10.1007/978-3-030-92377-8\_2

Fig. 2.1 Publications on global migration history compared to global migration, migration control, and migration management

Protestants—Huguenots—fled from France in the seventeenth century, after their right to exercise their religion was revoked, and many thousands had been killed. They fled to the Dutch Republic (and to Dutch colonies in South Africa, the Dutch East Indies and the Caribbean), England and Wales, Switzerland, Brandenburg, the Palatinate, and Prussia. They are remembered as the welcome immigrants because they strengthened Protestantism, and brought with them skills, money, and networks. However, when not all Huguenots proved to be as wealthy as the authorities had hoped they would be, the refugees were forced to set up their own churches (separate from the existing Calvinist churches) so that they could support their own poor (Briels, 1985; Gelderblom, 2002). Some of the Huguenots were welcome, others much less so. And this is similar for the migrants of today.

Today's migrants come from and go to different countries than they did in the past. Over time, migration routes have always changed and shifted; there is continuity in change, and change in itself is nothing new. When comparing the present to the past it is important to keep in mind that currently the distances that are travelled are generally longer and the frequency of travel is higher, but the number of hours spend travelling is not: it took 3 weeks to cross the Atlantic from Europe to the US at the beginning of the nineteenth century, 5 days at the end of the nineteenth century, and 8 h now (Feys, 2016). Travel became faster, safer and cheaper and this meant that overall mobility increased (not only that of migrants). Furthermore, also knowledge 'travelled' faster and more easily. This begs the question which indicators we should use to compare the migrants of today to those of the past.

Overall, there is a strong Western-centric bias in the literature. Migrations to, within and from Asia and Africa are largely presented as the results of what Europeans did or did not do (Bosma et al., 2013; Lucassen, 2004). Many of the migration histories about Africa, for instance, start with European colonisation (cf. Asiwaju, 1976). This obscures the fact that there were migration trajectories that started before Europe took control, and which continued after the Europeans arrived. Contact between the Indian subcontinent and East Africa, for instance, goes back 2000 years. When Vasco da Gama arrived in Mozambique, Mombasa, and Malindi in 1498, he was surprised at how many Arabs and Indians he found there (Oonk, 2013; Dussubieux et al., 2012). There was also migration from Hadramawt (currently in Yemen) which started before the time of Mohammed and continued for centuries after (700–1500). It connected the Red Sea and the Persian Gulf to the African shore (Bahl, 2017; Martin, 1974; van den Berg, 1886). Students from the Horn of Africa were studying in Cairo since the Middle Ages, and the students were following in the footsteps of traders and vice versa, over centuries (Loiseau, 2019). Multiple other examples of migrations that started before colonisation, and continued after it began could be given.

From the sixteenth century onwards, European colonisation disrupted existing migrations and later colonisers rather randomly drew international borders on the world's map, making people into to cross-border migrants although their migration routes did not change. Since the borders were important to the colonisers, but not per se to the colonised, some authors have argued against the use of the term 'migration' (which holds the implicit assumption that state borders are important), preferring the term 'mobility' instead. This so-called mobility turn approach underscores the need to make clear which boundaries matter to whom, when and why.

The literature pays too little attention to continuities. For instance, there were already in the nineteenth century large and long-standing Chinese immigrant communities in South Africa, Mauritius, Reunion and Madagascar (Neame, 1909). The nature of the Chinese migration to the African continent did change over time. In the 1950s to 1970s, the People's Republic of China promoted and organised migrations to African countries as part of its anti-imperialist policy of co-operation and solidarity with, what was called at the time, the Third World. In the 1980s, the number of migrants in African countries from Hong Kong and Taiwan increased, followed by an increase in the numbers from mainland China. In 2008, there were 700–800 Chinese companies in Africa employing 80,000 Chinese workers (Mohan & Tan-Mullins, 2008; Mung, 2008). It is correct to say that migration from China to Africa today is different from what it was 200 years ago. However, it is not as new as it is often made out to be.

The literature about the migration of men is still much larger than that about women, despite efforts to remedy this bias (for an overview, see Schrover & Moloney, 2013). Migration researchers and policymakers endlessly repeat the claim that a feminisation of migration has taken place (see, e.g., King & Zontini, 2000; Oso & Garson, 2005; El-Cherkeh et al., 2004; Kawar, 2004; OECD SOPEMI, 2001; Wihtol de Wenden, 2003). It is presented as one of the key characteristics of current migration (Castles & Miller, 2003, pp. 7–9, 188). Authors generally offer no proof for feminisation except the observation that women today form about 50 percent of the migrants. Although this is true, it was also true for many other migrations worldwide in much earlier periods, for which we have reliable data (Schrover, 2013). The claim that a feminisation has taken place in recent years, is followed by observations regarding migrant women's health hazards, the problems of women work, and to issues such as prostitution and trafficking (Wihtol de Wenden, 2003; El-Cherkeh et al., 2004; Yamanaka & Piper, 2005; Dobson, 2008). The rhetoric about the feminisation of migration is part of, on the one hand, attempts to generate attention for the understudied migration of women, and on the other hand, it is part of the problematisation of migration (Schrover, 2013).

Over time, people moved because they had to, wanted to, were allowed to, or were forced to. They were driven out by poverty or saw better economic opportunities elsewhere. They were seeking adventure, luck, love, a family and freedom, or they fled repression, war, persecution, and disaster. Motives for moving have been the same throughout history. Frequently, reasons to move overlapped: people fled, but they directed their steps toward a country that offered both freedom and economic opportunities. Currently, there is attention for 'climate refugees'; people who move because of drought, floods, or other environmental disasters. However, also that migration is not new. In April 1815 Mount Tambora in Indonesia erupted, and a veil of volcanic dust wrapped around the Earth, blocking the sun in 1816, 1817, and 1818. It led to 3 years without a summer and floods, droughts, storms, the spread of disease, and failed crops, thousands of kilometres away from the eruption site. Hundreds of thousands of refugees took to the road, trying to escape poverty and hunger (D'Archy Wood, 2016). Attention to 'climate refugees' is new, but the migration itself is not.

Lastly, the assumption has been made that the number of immigrants today is larger than in the past. To some measure this is true. The absolute number of people living outside their country of birth increased from 93 million in 1960 to 244 million in 2016. However, this increase is in line with the growth of the global population, which grew from 3.0 billion in 1960 to 7.5 billion in 2016. The global share of people living outside their country of birth is 3 percent now as it has been in the last six decades. Within the EU, the percentage of people born in another country is larger (57 million or 11.3 percent of the population) than ever before. However, 20 million of these migrants come from other EU countries. Within the EU there is free mobility and encouraging this has been a goal since the Treaty of Rome was signed in 1957. The migration within the EU has become more like internal migration. If we look percentages on a worldwide scale, migration has not increased.

#### 2.2 Who Counts?

There is an extensive debate about numbers when it comes to global migrations. As said above, migrations from, to, or within the Western world, have over time been described much more than other migrations.1 Attempts have been made to remedy that unbalance, but it still exists (Bade et al., 2011; Ness et al., 2013; McKeown, 2004, 2010; Moya & McKeown, 2010). One reason for it is a lack of data. Many migrations in the past went unrecorded. The further away from the Western world, and the further back in time, the more difficult it becomes to estimate the number of

<sup>1</sup> https://www.migrationpolicy.org/article/todays-immigration-policy-debates-do-we-need-littlehistory

people on the move. In part this has to do with definitions (Who is a migrant? Which borders are relevant?) (Urry, 2010; Cresswell, 2010; de Bruijn, 2014), and in part with authorities caring less about certain categories of migrants. States were as a rule more interested in men, as taxpayers and potential soldiers, than in women (Schrover et al., 2008). In the nineteenth century, German states forbade the migration of women who were planning to leave their children behind, but not of men who were planning to do the same (Schrover, 2001). Women left despite the restriction, but without being registered. Under-registration was influenced by gender as well as by skin colour. In the period 1946–1970, 617 thousand white people migrated to South Africa, 39 percent of them from the UK and 41 percent from other European countries. Between 1913 and 1986, black people could only enter South Africa illegally or as contract workers. They came mainly from Mozambique, Lesotho, Swaziland, Botswana, Zimbabwe, and Malawi (Peberdy, 1999). The white migrants to South Africa were recorded, but the black migrants—who mostly could not move legally—were not. The lack of data is a result of a lack of interest, a deliberate choice to not register some people, and restrictions on the migration of some of the people (Manning, 2005, 2006; van Schendel & Abraham, 2005).

One problem with historical sources relating to non-Western countries is that many of them have been made by colonial authorities, or organisations strongly aligned to them. This, however, does not mean the information has to be discarded. A critical view on who collected material, when, and why is standard practice for historians. Information that has been gathered by colonisers can still provide us with information about the colonised, and others. Furthermore, part of the material remains underused because the focus in research is on movement between the Metropolis and the colony. Other movements receive less attention, although information is available. For instance, in 1952, the British made plans to resettle the Kazakhs, who had fled from Tibet to Kashmir, in Turkey, and in 1955, British authorities made a plan to resettle Chinese refugees in Hong Kong in Paraguay.<sup>2</sup> A Eurocentric focus on working with these types of sources often means these migration plans are ignored.

Regime changes lead to breaks in data collections. For the Russian Empire-USSR there is, for instance, a gap between 1920 and 1990 (Siegelbaum & Page Moch, 2014). From the mid-nineteenth century to the early twentieth century, the Imperial Russian Government, which included eastern Poland and Finland, had consulates throughout North America. These consulates collected data on migrations from the Russian Empire to the US and Canada. An online database provides access to about 11,400 references to the passport and identity papers. After 1920 this information stops, because of the Russian Revolution and the creation of the Soviet Union. From 1990 onwards, data about migration in the (former) USSR are again available.<sup>3</sup> Data

<sup>2</sup> http://www.archivesdirect.amdigital.co.uk/

<sup>3</sup> USSR statistics on migrations in the period 1987–2009 https://docs.google.com/spreadsheets/d/1 QKWkxJaBDYXGmWuZUMg-fLE0iIKMyzvhPCknp\_4NQZk/edit?hl¼en\_US&hl¼en\_ US#gid¼0

for the gap in between can be pieced together. The Electronic Repository of Russian Historical Statistics, for instance, brings together data extracted from various published and unpublished sources with a focus on Russian history from the eighteenth until the twenty-first century.<sup>4</sup>

When it comes to global migrations, it is interesting to have data covering long periods of time. These types of data have been collected, for instance, via censuses, and by SOPEMI (Système d'Observation Permanente sur les Migrations), by Ferenczi and Willcox, and in the UN's Demographic Yearbooks (Salt, 1989).

Statistics that relate to nationality (i.e. in the censuses) are problematic because migrants can and do sometimes have more than one nationality, and it is often not clear how these migrants were dealt with in statistics. Data on flow (arrivals and departures) make it possible to see year-to-year changes. Not all countries, however, use the same length of stay as a measure to distinguish migrants from, for instance, tourists, and the indicators used tend to change over time (Simmons, 1987). A matrix of data on migration, constructed in 1972, showed that figures for a particular flow reported by the country of immigration were substantially higher than the figures for the same flow reported by the country of emigration (if data were correct and immigrants were defined in the same manner the numbers should be the same). Of the 342 flows between pairs of countries in the matrix the total reported number of immigrants was 57 percent higher than that of the number of emigrants (1,072,500 versus 683,200) because countries used different definitions of migrants with varying measures for the minimum duration of stay (Kelly, 1987).

In 1973, SOPEMI was established to provide the European Member States of the OECD (Organisation for Economic Co-operation and Development) with mechanisms to share information on international migration. SOPEMI annually publishes Trends in international migration.<sup>5</sup> Data in these reports are not comparable (as is true for all other sources) (Salt, 1987).

Imre Ferenczi and Walter F. Willcox, in their 1929 publication International Migrations published data on migrations in the nineteenth and twentieth century. Imre Ferenczi was the Technical Adviser on Migration and Population Questions at the International Labor Office (ILO) in Geneva since 1920, and acting chief of its Migration Section. The emphasis in this work is on emigration, mostly from Europe, but it includes a wealth of other data. The ILO has collected massive data on labour migration, since 1920, and this includes extensive data for labour migrations between African countries during colonialism.<sup>6</sup>

<sup>4</sup> https://ristat.org/topics#

<sup>5</sup> http://www.oecd.org/general/trendsininternationalmigrationreflectincreasinglabourrelatedimmigrationandpersistentintegrationproblems.htm

<sup>6</sup> https://ilostat.ilo.org/data/

#### 2 Migration Histories 31

For the last 60 years of the twentieth century, data can be extracted on immigration to European countries from the United Nations Demographic Yearbooks (UN, 1949; 1951; 1953; 1955; 1958; 1960; 1963; 1967; 1971). The tables in the Yearbooks come with very long explanatory footnotes regarding the comparability of numbers. In the Demographic Yearbooks data on flow (arrivals) are only available for some countries over any length of time. Albania, Bulgaria, the German Democratic Republic, Greece, Malta, Romania, and the USSR never supplied data on immigration or emigration well into the 1980s or later. Data on Eastern European countries and the USSR are missing for almost all years, except the most recent. Portugal only supplied data on emigration, not immigration.

The data in the UN Yearbooks and other sources only include people who were regarded as foreigners. This means that people who returned from former colonies, such as the pied noirs in France and repatriates in the Netherlands, are not included, and neither are the Aussiedler or Spätaussiedler who came to Germany. Since 1950, 4.5 million Aussiedler or Spätaussiedler moved to Germany, about half of whom came from the Soviet Union and successor states. In recent years, new EU Member States mirrored these policies of return and gave preferential rights to 'returnees', frequently descendants of people who left generations ago, or were deported under Soviet and communist rule. Poland grants rights to co-ethnic returnees from Kazakhstan; Greece for co-ethnic returnees from the former republics of Georgia, Kazakhstan, Russia, and Armenia; and Hungary does so for co-ethnics from Romania, Ukraine, and former Yugoslavia. Numbers are substantial. Finland, for instance, encouraged 60,000 Ingrian Finns to 'return' from the former Soviet Union. In statistics they are frequently not visible.

As said, the information on older migrations is scant. There are exceptions. There is for instance an interactive map portraying Jewish migrations during Antiquity.<sup>7</sup> Furthermore, there is a digital collection of so-called prize papers: documents pertaining to tens of thousands of seized ships ("prizes") making it possible to analyse who travelled on them in the Early Modern and Modern period. An option in the Map Tool allows users to see in what places emigrant sailors from Scandinavia ended up,<sup>8</sup> or from where for example Boston drew its foreign sailors.<sup>9</sup> It can identify the birthplaces of illiterate mariners,<sup>10</sup> or generate a visual representation

<sup>7</sup> https://www.pbs.org/wnet/story-jews/explore-the-diaspora/interactive-map/

<sup>8</sup> https://prize-papers-atlas-online.brillonline.com/map;jsessionid¼F7256C8A52853E1EB25E2 DCF7DE06D1D?bpl\_country¼Sweden%20or%20Norway%20or%20Denmark%20or%20Fin land&res\_country¼not%20Sweden%20not%20Norway%20not%20Denmark%20not%20Fin land&searchfilter¼res <sup>9</sup>

https://prize-papers-atlas-online.brillonline.com/map;jsessionid¼F7256C8A52853E1EB25E2 DCF7DE06D1D?or\_place¼Boston,%20MA&bpl\_country¼not%20United%20States%20of%20

America&searchfilter¼birth 10https://prize-papers-atlas-online.brillonline.com/map;jsessionid¼F7256C8A52853E1EB25E2 DCF7DE06D1D?crewlit¼Cross&searchfilter¼birth&iconsizefilter¼small

of the places of residence of married seamen.<sup>11</sup> The data are enormously rich, but they cover only a small percentage of the migrants.

For recent periods there is much more material to work with. Information about migration to the US is especially abundant. Shipping companies, rather than state authorities, collected data on who migrated across the Atlantic (Feys, 2010; Brinkmann, 2008). Much of the material of the shipping companies is available digitally.<sup>12</sup> Furthermore, digitised information is available (also visualised in maps) about everybody who migrated to the US since 1820.<sup>13</sup> For the US there are in addition large online archival collections on migration.<sup>14</sup> This includes the 1911 full report of the US Dillingham Commission (41 volumes) on migration, with extensive data on immigrant groups in the US. The Library and Archives of Canada similarly hold immigration records and travel guides, passenger lists, letters, diaries, journals, memoirs, newspapers, maps, art, photographs, music, and films.<sup>15</sup> The Immigration History Research Center Archives in Minneapolis holds an enormous amount of information on immigration, including digitised immigrant letters.<sup>16</sup> There is also systematic information on, for instance, migration to and from Germany in the period 1950–2017.<sup>17</sup>

The World Economic Forum published an interactive map covering the period 1990–2017 and including migrations to the US from all countries in the world.<sup>18</sup> Similar information is provided based on data from the UN Population Division, providing a map with the net number of migrants per country for the period 1950–2015.<sup>19</sup> The Migration Policy Institute has mapped the largest refugee populations by country of destination for the period 1960–2019. The map displays which countries report refugee populations greater than 500,000 in each decade since 1960 and in 2015 and 2019. Furthermore, it lists the 25 largest refugee populations by the country of destination and the refugee share of the total

<sup>11</sup>https://prize-papers-atlas-online.brillonline.com/; https://prize-papers-atlas-online.brillonline. com/map;jsessionid¼F7256C8A52853E1EB25E2DCF7DE06D1D?crewmarstat¼Married& searchfilter¼res&iconsizefilter¼small 12Database for new arrivals on Ellis Island in New York:

https://www.libertyellisfoundation.org/

<sup>13</sup>http://metrocosm.com/animated-immigration-map/ The same information is also used for other

websites: http://dsl.richmond.edu/panorama/foreignborn/#decade¼1960&country¼Germany 14For instance: https://curiosity.lib.harvard.edu/immigration-to-the-united-states-1789-1930?utm\_ source¼library.harvard 15https://www.bac-lac.gc.ca/eng/discover/immigration/Pages/introduction.aspx

<sup>16</sup>https://www.lib.umn.edu/ihrca

<sup>17</sup> https://www.destatis.de/DE/Themen/Gesellschaft-Umwelt/Bevoelkerung/Wanderungen/ Tabellen/wanderungen-werte-.html

<sup>18</sup>https://www.weforum.org/agenda/2017/05/diversity-in-the-us-mapped

<sup>19</sup>https://www.migrationpolicy.org/programs/data-hub/charts/net-number-migrants-country-1950- 2015-five-year-intervals?width¼1000&height¼850&iframe¼true

population.<sup>20</sup> The UNHCR provides historical refugee data from 1960 onwards.<sup>21</sup> The flow of people across the world in the period 1990–2010 has been mapped, this time trying to take a global approach.<sup>22</sup>

Overall, there have been numerous projects on mapping human migration across time and space, although mostly focused on recent migrations (Zambotti et al., 2015).

#### 2.3 A Helicopter View

This section will provide a helicopter view of global migrations, focusing on major moves. As long as there are people, there has been human migration, starting with the migration of Homo sapiens across the African continent 300,000 years ago, their dispersals to the southern coast of Asia and Oceania 70,000–50,000 years ago, and into Europe 40,000 years ago. As with all later migrations, also the 'Out of Africa' migration has led to extensive debates about when, in which numbers, how and why people migrated. Currently climate change is being offered as an explanation for why the homo sapiens' started to move (Rito et al., 2019). The 'Out of Africa' migration led to the creation of several interactive maps.<sup>23</sup> The Interactive Human Migration Map retraces the paths of the first humans across the world.24

Skipping ahead ten thousands of years, brings us to the period between 3000 and 2000 years ago, when 60 million Bantu speakers from West and Central Africa, moved South and East across the African continent. Linguists, archaeologists, and DNA specialists provided the information, which allowed for the reconstruction of this large-scale migration (de Luna, 2014; Li et al., 2014).

From 500 BCE onwards the Silk Road started to develop, which connected Southern Europe to East Asia, with traders, troops, scholars, goods, and ideas moving from East to West and vice versa. Imperial Rome, in turn, housed migrants from all parts of the Roman Empire, including Gauls, Spaniards, Syrians, Persians, Britons, Greeks, Libyans, and Egyptians, as well as migrants from India and Africans from unspecified countries. After the onset of decline of the Western Roman Empire, 750,000 Germanic people moved into the Roman Empire. The number of these migrants, and the nature of the migration, are highly contested (Geary, 2012). Their migration is usually presented as a destruction narrative, in

<sup>20</sup>https://www.migrationpolicy.org/programs/data-hub/charts/largest-refugee-populations-country-

destination?width¼1000&height¼850&iframe¼true 21https://data.unhcr.org/en/search?type%5B%5D¼document&global\_filter%5Bdoc\_type%5D%

<sup>5</sup>B%5D¼7&maps¼<sup>1</sup> 22http://download.gsb.bund.de/BIB/global\_flow/

<sup>23</sup>See the interactive maps to illustrate this https://www.pbslearningmedia.org/resource/interactive-human-migration-map/interactive-map/ http://atlasofhumanevolution.com/Maps.asp

<sup>24</sup>https://www.pbslearningmedia.org/resource/interactive-human-migration-map/interactive-map/

which Germanic masses immigrated from the North and East into Central Europe, causing the end of the civilised world of classical antiquity (Wiedemann, 2020). The same destruction narrative is applied to Muslim migrations into Europe from the South, and Vikings coming from the North, from the eighth century onwards. The Vikings reached the Mediterranean and North America, and the Muslims governed most of Spain and Portugal. In the same period there were also other large migrations. In the nineth and tenth century, for example, large numbers of people moved South in what is now China and mixed with the Han people already living there. There is no consensus on how large these various groups of migrants were (Hoerder, 2012).

As is true for today, also in the past motives were mixed. As a rule, pilgrimage and trade intertwined (Bahl, 2017). West African Muslims, for instance, travelled to Mecca already in the early twelfth century. Rulers of Mali made the pilgrimage in the 1260s. Most famous was Mansa Musa, who made his pilgrimage with 60,000 people in 1324, as witnessed and recorded by Italian traders. Mansa Musa was born in 1280 and ruled the kingdom of Mali from 1312 to 1337. His regime controlled the routes to the Bambura and Bambuhu gold fields. His fame, especially because of his pilgrimage, led to stories in the Middle Ages in Europe and the Arab world about an Island of Gold in central Africa (Keech McIntosh, 1981). Many explorers set out to find it, paving trade routes while doing so (Masonen, 1997).

Between 1547 and 1860, European ships carried 11–14 million enslaved people from Africa across the Atlantic (Lofkrantz & Ojo, 2012; Matlou, 2013). African people were also brought to Asia as enslaved people. It is estimated that between 800 and 1900, 12 million enslaved people were transported across the Red Sea and the Indian Ocean. This migration started earlier – in 2900 BC when Nubian captives were moved to Egypt – and continued longer. Between 800 and 1600, 4.7 million enslaved people moved North across the Sahara, and 2.7 million did so between 1600 and 1900, part of whom were moved East from there (Ralph, 1992). The literature on this forced movement is overshadowed by that on the transatlantic slave trade, also in the debates about numbers (Collins, 2006). After the formal abolition, slavery was partly replaced by indentured labour. In total, 1 million indentured workers were brought from India to the Caribbean (Lal & Jahaji, 2000; Kaur, 2012).

In the second half of the nineteenth century and the first decades of the twentieth migration increased. Between 1840 and 1940, 60 million people left Europe, 21–23 million left South China, 30–33 million moved from China to Manchuria, 43–50 million moved within or left India, 20–40 million moved within China, 9–13 million left from the Eastern Mediterranean and Western Asia, 74 million moved within Europa and 35 million within the Americas (Moya & McKeown, 2010; McKeown, 2004; Gottschang, 1982). Over 4 million people left Ireland between 1841 and 1911. Between 1846 and 1932, 52 million people in total left Europe. Between 1880 and 1914, 4.3 million Russians migrated to Siberia (Anderson, 1980). In 1910, there were officially 111 thousand of Chinese subjects in Russia (according to estimates, there were 1.5–2 times more). In 1923 there were 250 thousand Russians in China (according to some authors, 400 thousand—see Kireev 2016)). In 1907, after a treaty had been concluded between Japan and Brazil, thousands of people moved from Japan to Brazil, mostly to work on coffee plantations (Tsuda, 2003). Overall numbers were higher than in previous eras.

Mobility increased because travel became cheaper, faster, and safer (after the introduction of railroads and steam ships). It affected travel all around the world (Feys, 2010; Neyens, 2016), including crossing the South Chinese Sea and the Arabian Sea (Kaur, 2009). This led to a sharp rise in the number of pilgrims from the European colonies in Asia to Mecca; a trip that previously had been made by much fewer people, and also a trip from which many did not return because they died on the way (Moch Nur, 2008; van Bruinessen, 1995). The number of pilgrims returning led to a rise in pan-Islamism, which created fears among colonial authorities, who in response started to register and monitor pilgrims much closer than before.

After the start of the Russian Revolution in 1917, 1–2 million Russians fled (Simpson, 1939). During the First World War, 20 million people became refugees and internally displaced persons in Europe (Lissner, 1977). In the First World War, there were large-scale forced migrations. Germany deployed 1.5 million Prisoners of War (POWs), and Austria-Hungary put to work more than 1 million Russian POWs. 2.1 million Austrian-Hungarian and 0.17 million German POWs worked in Russia, and tens of thousands of German POW worked in France and Britain. In 1916, the German occupation forces deported 5000 Polish workers from Lodz, mostly Jews, and 61,000 Belgian workers to Germany. Part of these migrations or deportations were meant to be temporary, but they ended up to be permanent, because POW stayed or died in the countries they were brought to.

Immigration restrictions, introduced in the US in the 1920s, greatly reduced migrations to the US. Other countries that received large numerous migrants in the past decades followed suit (Cook-Martin & Fitzgerald, 2010). The onset of the economic crisis of the 1930s reduced possibilities for labour migration, although not all labour migration came to a halt. In France employers cooperated in a Société Générale d'Immigration, which between 1920 and 1930 recruited 490,000 Polish migrants, to work as miners (Knotter, 2015). In the 1920s and 1930s, the discovery of oil led to migrations into the Gulf region. The migrants were senior staff of the oil companies from the US and UK, high-skilled workers from India, and low skilled migration form countries in the region (Errichiello, 2012).

In the 1930s there was a sharp rise in refugee migration. Poles fled in large numbers, as did the Chinese, and 500,000 Spaniards fled to France during the Civil War. After Hitlers rise to power, Jews and others sought to escape Nazi Germany. During the Second World War, the scale of forced labour migration increased dramatically. Two Soviet decrees of 1942 forced 316,000 ethnic Germans living in the Soviet Union into so-called labour armies and moved them to far away sites to cut timber, build factories and railroads, work in coal mines, and in oil industries (Mukhina, 2014). In 1944, Soviet leader Joseph Stalin accused the Chechen people of helping the Nazis and forced 700,000 people to migrate to Central Asia. During the Second World War, Japan established a forced labour regime and deported 1 million Korean men and women and 40,000 Chinese to Japan. Many more examples of these large forced migrations could be given.

In Nazi Germany differences were made between forced labour migrants. The German word for guest worker—Gastarbeiter—was coined in Nazi Germany in order to distinguish the more or less voluntary temporary labour migrants form other migrants – Zwangsarbeiter and Ostarbeiter - who were forced to migrate and work, and who were deemed racially inferior and not capable of doing all tasks (Herbert, 1986; Didier, 1943; Hachtmann, 2010). Between 1939 and 1945, there were 13.5 million foreign forced labourers in Nazi Germany, of whom 12 million were coerced to move (Spoerer & Fleischhacker, 2002).

The Second World War created 60 million refugees worldwide, 30 million of whom in Europe (Davies, 2006). After the war, most of the European refugees returned home voluntarily. However, some of the people refused to return to their countries of origin. Poles, "Balts"—Estonians, Latvians and Lithuanians—and Jews comprised the three largest groups among them (Dinnerstein, 1982). The UNHRC states that its 'most recently estimated for 30 June 2020 shows that, for the first time in recorded history, the number of people forcibly displaced is now 80 million, and over 26 million refugees.' The data for the period around the Second World War provided above and below question this observation.<sup>25</sup>

In the immediate post-war period, there were, in addition to the 60 million refugees, 14 million Displaced Persons (DPs) in Europe, plus 12–16.5 million expellees (ethnic Germans from countries that had been under Nazi rule and who were expelled to Germany after the war) (Cohen, 2011). The expellees were explicitly defined as non-DPs and non-refugees by the parties discussing an international solution to the DP or refugee problem (Schrover, 2015). In addition, there were other movements. The Partition of British India in 1947 into India and Pakistan, for instance, displaced 17 million people.<sup>26</sup>

In the post-WWII years, authorities in Western European countries regarded their countries as too full. There were severe housing shortages, and it was feared that the pre-war unemployment would return. In the US it was feared that dissatisfaction would increase the support for communism in Western European countries. European authorities therefore encouraged emigrations from Europe. About 2 million people migrated to Australia in the immediate post-1945 years from the UK, the Netherlands, and Germany. From Germany 80,500 people migrated to Australia as labour migrants (Schmortte, 2005; Jones, 2002), and 200,000 to Canada between 1951 and 1957 (Schmalz, 2000). From the Netherlands about 400,000 people left. Most of these post-war European emigrants moved within assisted passage schemes: this means that their journey was paid by their country of origin, provided they had been selected for emigration (Schrover & van Faassen, 2010). Authorities encouraged, organised and financed large-scale mobility.

The countries of origin selected the people whom they thought they could miss, and countries of settlement such as Australia selected the people whom they wanted

<sup>25</sup>https://www.refugeecouncil.org.au/how-many-refugees/#:~:text¼UNHCR%20most% 20recently%20estimated%20for,and%20over%2026%20million%20refugees.

<sup>26</sup>For an oral history archive and interactive map see: https://www.1947partitionarchive.org/

to come. Bilateral treaties regulated the support the migrants got before, during and after their journey, as well as the criteria for selection. Over a four-year period, Australia entered into agreements with Italy and the Netherlands in 1951, Austria, Belgium, Greece, Spain and West Germany in 1952, and with Denmark, Finland, Norway, Sweden, Switzerland and the United States in 1954. In 1955 Australian authorities, implemented 'Operation Reunion' which was intended to assist family members to migrate to Australia. Within a decade, 30,000 people migrated from countries such as Bulgaria, Czechoslovakia, Hungary, Poland, Romania, the Soviet Union and Yugoslavia. Canada in a similar manner sought to attract people from Europe.<sup>27</sup> In the period 1946–1980, 4.8 million people migrated to Canada, including 1.1 million from Great Britain, 0.5 million each from the US and Italy, 326 thousand from Germany and 185 thousands from the Netherlands.<sup>28</sup> Ideas about how to best organise emigration from North-Western European countries in the 1950s - via bilateral treaties and based on selection – formed the blueprint for the organisation of guest worker migration a few years later. Civil servants organising emigrations, moved to new positions in which they organised the new immigrations. Countries were different but underlying ideas were the same.

In the period of 1958–1972, about 8 million work permits were issued to guest workers to work in Belgium, France, Italy, Luxembourg, the Netherlands, and West Germany. Initially, they were recruited to fill vacancies in mining and the steel industry, and as a result 80 percent of the guest workers were men. It led to a masculisation of migration, although the word was never used, not at the time, nor in later publications. In the UK, which was outside the European Coal and Steel Community (established in 1951) and the European Economic Community (est. 1957) workers from its (former) colonies were used in as similar manner to fill vacancies.

Authorities emphasised the circular nature of the guest worker migration to pacify the labour unions, who feared that the guest workers would stay and compete with local workers, when economic growth would slow down. The emphasis on the temporariness of the guest worker migration was a way to make this migration acceptable, so shortly after hundreds of thousands of people had been stimulated to migrate from Europe. When the guest worker migration system came to an end in the mid-1970s, guest workers reduced the number of trips back and forth, fearing (correctly) that they would not be able to re-enter the recruiting countries once they had left. The economic crisis, which was the reason to stop the recruitment of guest workers, also hit the countries of origin. Migrants did not want to return to their countries or origin in the midst of an economic crisis, and especially when this coincided with a period of political instability (Grotti & Goldstein, 2005).

Among the labour migrants there were people who could have applied for refugee status but did not: people were fleeing the regime of Franco in Spain, of Salazar in

<sup>27</sup>https://www150.statcan.gc.ca/n1/pub/11-630-x/11-630-x2016006-eng.htm

<sup>2 8</sup> http://faculty.marianop olis.edu/c.belanger/QuebecHistory/readings/ SourceofCanadianImmigrtants1921-1945.html

Portugal, the Colonels regime in Greece, the coups in Turkey and the repressions in Morocco. Most of them simply chose to move as labour migrants, which was easy under the guest worker migration regime. Those who did apply for refugee status were turned down and allocated by the authorities to the category of labour migrants (Walaardt, 2013).

East Germany also had a guest worker migration regime, albeit with smaller numbers of labour migrants than West Germany. Labour migrants were called ausländischen Werktätigen and Vertragsarbeiter. Until the German reunification, there were 69,000 Vietnamese, 50,000 Poles, 40,000 Hungarians, 25,000 Cubans, 22,000 migrants from Mozambique, 8000 from Algeria, 2000 from Angola and several hundreds from China and North Korea. About 70 percent of them were men. Bilateral treaties were concluded between the countries of origin of the labour migrants and the DDR (Rabenschlag, 2014; Ireland, 1997). In the 1980s, there were in total 300,000 mostly unskilled workers who worked in Communist Bloc countries, including the Soviet Union, Bulgaria, Czechoslovakia, and East Germany (Schwenkel, 2014). Although the East and the West of Europe seemed to be worlds apart, the way labour immigration was organised was not that different.

Between 1942 and the 1960s, the US had the rather similar the so-called Bracero Program, which regulated migration from Mexico (Blank, 2013). Canada also had a similar programme for the recruitment of temporary workers, mainly from the Caribbean. The Bracero Program was established in 1942 as a temporary wartime measure. It was extended by US Congress and expanded in the latter half of the 1950s. The migration was meant to be temporary and circular, as the labour migration in Europe was perceived to be. In the period 1955–1959, half a million Mexicans were entering the USA each year. In total the program brought 4–5 million people into the US, 89 percent of whom came from Mexico and 4 percent from the British West Indies or Jamaica (Massey & Pren, 2012).

Organised labour migration, based on selection, did not stop after the economic crisis of the 1980s. In the Philippines, the government since the 1960s organised the 'export' of nurses to other countries, hoping that remittances would stimulate the Philippines' economy (Yeoh et al., 1999; Panayiotopoulos, 2005; Urbano, 2012; Nesadurai, 2013). This continued beyond the period of guestworker migration. Currently, the total number of overseas workers from the Philippines is 10 million, of whom 3.5 million are in the US and 1 million in Saudi Arabia. The remittances of the Overseas Contract Workers—the official Philippine policy category—constitute 30–40% of the Philippine's BSP (McKay, 2007).

The economic growth that led to the migration to North-Western Europe, also caused the migration of large numbers of construction workers to the Middle East, during the oil boom of the 1970s and 1980s (Dito, 2013). Furthermore, in the 1960s, Mauritania, Ghana or Côte d'Ivoire attracted Senegalese, Malian, Guinean and Gambian migrants to fill vacancies. In 1969, after the 1966 coup, Ghana expelled 155,000–213,000 immigrants, mainly from Nigeria, Togo, Burkina Faso and Niger. In 1983 and 1985, during the economic crisis, Nigeria similarly expelled two million west-African migrants, mostly Ghanaians, who had come during earlier periods of economic growth. In the 1970s and 1980s, people from Mali, Niger and Chad migrated to construction sites and the oil fields in Algeria and Libya (de Haas, 2007).

As before, there were refugee migrations as well as other migrations. In 1962, Chinese refugees fled to Hong Kong at a rate of 2000 per day. In 1967, 1.8 million people fled from other parts of Nigeria to Biafra, after persecutions and mass killings. After the start of the Civil war in 1968, Nigerian authorities tried to starve the Biafran population to death, resulting in the death of 1000 children per day at the hight of the conflict. Some of the Biafrans fled to neighbouring countries, but most were unable to do so. In 1971, after the start of the war between India and Pakistan, 10 million people fled from Pakistan (Bangladesh) to India. In the 1970s, 1–2 million people fled from Vietnam, and in the 1980s 2.5 million people fled from Afghanistan. The outbreak of the civil war in Yugoslavia in 1991 led to new refugee migration in Europe. By August 1992, approximately 2.5 million people had fled their homes as fighting in the Balkans spread. Almost 2 million were displaced within former Yugoslavia and 633,938 sought asylum in Western European countries by 1994 (Helfer, 2006). The civil war in Syria, which began in 2011, led to the displacement by 2018 of 6.6 million people within Syria, while 5.6 million were registered as refugees in neighbouring countries. Between 2011 and 2017, over one million Syrians applied for asylum in the EU.

#### 2.4 Conclusion

The brief overview presented above, with its dazzling numbers, makes clear that global migration is by no means new. The largest problem with the literature on global migrants in the past is that it is Western-centric, as has been observed above. The reason for this is that there is much more source material on migrations to or from Western countries. The material that is available is frequently not studied from a comparative perspective. This creates the image that migration to, from, and in the West, was and is different from that in the rest of the world. Awareness of these biases will help us find new material, or look at existing material from a different perspective. The overview also showed the many aspects of how migrations were organised or problematised were not new either. Attempts to monitor, manage and control migrations always built on practices and ideas from the past. Lastly, the overview showed that numbers are rather unreliable (especially is who go further back in time, or away from Western countries), and that counting is influenced by gender, ethnicity and class. Yet, numbers are frequently used to claim the newness of current migrations.

#### Bibliography

Marlou Schrover is a Full Professor of Migration History and holds the Chair of Economic and Social History at Leiden University. She has more than 170 publications including 7 books and 5 edited volumes. She is also editor-in-chief of the Journal of Migration History. She frequently speaks in front of non-academic audiences and appears in the press regularly.

Open Access This chapter is licensed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license and indicate if changes were made.

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### Part II Conceptual Approaches: Migration Drivers, Infrastructures, and Forms

### Chapter 3 Migration Drivers: Why Do People Migrate?

Mathias Czaika and Constantin Reinprecht

Growing social and economic inequalities, and consequently, unfulfilled life aspirations trigger the migration intentions of millions, if not billions of people around the world. Surveys by Gallup World Poll suggest that more than 750 million adults would like to migrate if they had the chance to do so (Esipova et al., 2018). Hence, globally 'only' one in eight adults express a desire to migrate. This is a surprisingly small fraction given the fact that a much larger but unknown number of people would have good reasons to migrate in order to realise economic, professional, political, or social opportunities elsewhere. At the same time, only small fractions of those who aspire to migrate are actually able to realise it.

However, why do people want to migrate in the first place? At specific moments in people's lives a number of factors come together and stimulate migration intentions, which, given some achievable livelihood opportunities, may end up in temporary or permanent moves to another domestic or international destination. Factors that drive both migration intentions (and aspirations) and actual moves are manifold and multifaceted, and over the past decades, migration researchers have been identifying and describing numerous factors and contexts that shape both individual migration trajectories and broader migration processes. Researchers studying drivers of migration are hereby asking: what are relevant factors that are driving migration, and how do these drivers operate in time and space? To what extent and in what ways do they influence, i.e. trigger or hinder, migration decision-making of some people but not of others? Moreover, how do multidimensional migration drivers interact and create complex driver configurations that may affect some people more than others in aspiring and realising migration as a viable behavioural option?

A term that is often used in migration studies is migration determinants, suggesting a structural and 'deterministic', i.e. causal, relationship between some

Danube University Krems, Krems, Austria e-mail<EMAIL_ADDRESS>
M. Czaika (\*) · C. Reinprecht

<sup>©</sup> The Author(s) 2022

P. Scholten (ed.), Introduction to Migration Studies, IMISCOE Research Series, https://doi.org/10.1007/978-3-030-92377-8\_3

external factors and migration. However, this conception is rather misleading as it ignores the central role of human agency in migration processes (Bakewell, 2010; Carling & Talleraas, 2016) and the often indirect or intervening role of some contextual factors in a migration (decision-making) process. Root causes is another term widely used, particularly in policy circles, where root causes are mostly understood as 'the social and political conditions that induce departures - especially poverty, repression, and violent conflict' (Carling & Talleraas, 2016, p. 6). But also this concept of a migration-inducing factor is relatively narrow because it is rarely a single or specific fundamental causal factor that is setting people in motion. Rather, it is a number of factors that are mutually mediating and conjointly shaping migration decisions and broader migration dynamics and patterns. We therefore prefer the term migration drivers (rather than causes or determinants) of migration as 'structural elements that enable and constrain the exercise of agency by social actors' and make 'certain decisions, routes or destinations more likely' (Van Hear et al., 2018, p. 928).

At a higher level of aggregation, structural disparities between places, which may turn out as locations of origin and destination, create the context that make migration decisions more likely. These spatial disparities may reflect long-standing social and economic inequalities and gaps in living standards both within countries and internationally between, for instance, the global North and South—as well as cyclical or seasonal economic fluctuations. At lower levels of aggregation, i.e. at the meso- and micro-level, migration drivers facilitate or constrain migration by affecting perceptions about migration opportunities and influencing people's capacities to realise these opportunities. Consequently, people's perceptions about spatial opportunity gaps are necessary pre-conditions in people's migration decision-making.

Besides structurally embedded and therefore mostly slow-changing disparities in livelihood opportunities, specific events, and sudden developments, including some rapid policy changes, may both predispose and ultimately trigger migration. The complex interplay of multiple economic, political, social, and other gradual developments and sudden events may dynamically change migration opportunities for heterogeneous groups of people. The concept of complex driver environments, that is time-space-dependent configurations of multidimensional drivers that define people's willingness and ability to change life situations through migration, forms the theoretical underpinning of this chapter.

In the remainder of this chapter, we briefly outline some key, and by now, classical theories of migration that are often referred to in explaining migration outcomes. We then propose a taxonomy of 24 migration drivers, categorised into nine driver dimensions, and elaborate on the key features of their configurational interplay that characterises migration driver environments. Following that, we provide a meta-review of scholarly work on migration drivers and discusses the state of knowledge on person-specific, group-specific, and more macro-structural and external migration drivers.

#### 3.1 Migration Drivers: The Theoretical Basis

#### 3.1.1 Classical Theories of Migration: An Overview

The reasons why people migrate have been theorised and studied for decades and the scientific literature has identified a number of fundamental dimensions of migration drivers including economic, political, social, cultural, demographic, and ecological factors (for comprehensive reviews see Ghatak et al., 1996; Hagen-Zanker, 2008; King, 2012; Massey et al., 1993). We briefly outline some influential theories of migration including functional perspectives of migration being instrumental for income maximisation or historical-structural theories explaining migration as the result of class-based deprivations in (global) capitalist systems.

Neoclassical migration theory, based on Sjaastad's (1962) cost-benefit model and Lee's (1966) push-pull model of migration, suggests that individuals migrate due to the discrepancy in economic opportunities between those available at a destination and a lack thereof at the place of residence. The interrelated decisions of whether and where to migrate are linked to existence of substantive income or utility differentials between places. People tend to move if expected returns to migration are beneficial. Although Lee's push-pull model, as well as the augmented gravity model, explain overall migration flows between locations relatively well, these models have also been criticised for failing to explain why the majority of people do not migrate despite severe income differentials (Bogue, 1977; Hagen-Zanker, 2008). One reason for immobility is the fact that migrants are not simple pushed and pulled between places according to wage gaps or livelihood differentials, but people's own agency and self-determination decides whether and where to relocate (Bakewell, 2010).

Another critique of the neoclassical migration model is that it suffers from methodological individualism, i.e. it assumes that individuals are the main decision-making units. However, individuals belong to households and communities who influence or even take the decisions, or people may even move as a family. Scholars have therefore urged for a reconsideration migration decision-making, and two perspectives on the role of households have emerged (Boyd, 1989; Sell & De Jong, 1978). First, family structure and functions have both direct and indirect effects on migration decision-making but the individual remains the decisionmaker, and secondly, the family is the ultimate migration decision-making unit.

Harbison (1981) argues that family structure and function are not merely additional explanatory variables. Families transmit information and shape individuals' motivations, values, and ultimately migration norms, thereby directly and indirectly affecting migration decision-making. Further, structural and functional family characteristics affect the perceptions of costs and benefits associated with migration. However, it is unclear how potential intra-family dissent affects migration decisionmaking processes. Bargaining models explain family migration decisions by interrelated utility maximisations at the household and the individual level, respectively (Abraham & Nisic, 2012). However, bargaining do often not consider coordination and communication problems (Kalter, 1998).

The new economics of labour migration (Stark & Bloom, 1985) put the household or family at the centre of migration decision-making, arguing that households are able to diversify income risks and control uncertainty by allocating individual household members to specific income sources, and therefore, alternative migration options (Haug, 2008; Massey et al., 1993). Family ties embody important social externalities, which affect migration decision-making (Mincer, 1978). For instance, negative externalities, represented by strong ties to the place and people at origin, decrease the likelihood of migration. At the same time, family and friends living elsewhere establish positive externalities by transmitting valuable information that reduces migration-related uncertainty (Stark & Bloom, 1985). Externalities are also the driving force behind migration when relative rather than absolute deprivation is spurring migration aspirations, as people compare their own well-being, income and living standards to others around them (Stark & Taylor, 1989, 1991). More recent migration decision-making models have been adapted as they combine individual factors with a focus on the family or household (Anam & Chiang, 2007).

Network theory claims that migration as a social outcome is based on the complex interplay of decisions taken by individual actors, family and friends, migrant organisations, and other economic and political factors (Boyd, 1989). Social networks hereby influence not only whether and how migration takes place, but also where migrants are predominantly moving to (Haug, 2008). Ritchey (1976) states that people with access to relevant social capital incentivises migration by providing information, financial assistance, and practical support. However, Heitmueller (2006) adds that network effects can go in both directions, that is information provided through networks is not necessarily only positive but can also discourage migration. More migrants at a particular place has a positive community and family effect attracting more migrants to this destination. At the same time, local labour markets may saturate and wages might in turn decrease. Therefore, there might be a point where migrants in destination countries either withhold information or send even negative messages '[...] to hamper further migration' (Heitmueller, 2006, p. 706).

Network theory is also a useful perspective to understand the perpetuation of migration (Massey et al., 1993) and destination choice once migrant networks are established. However, network theory does also not explain migration when migrant networks are absent, or how migrant networks dissolve (de Haas, 2010). Epstein (2008) distinguishes between network and herd effects. Herd behaviour means discounting or disregarding private information to follow the behaviour of others. This is rational given the assumption that others base their decisions on better information (Epstein, 2002). Herd behaviour results in migrants following the flow rather than the stock (i.e. established network) of previous migrants. While herd effects cannot account for new, pioneering migration, they can explain migrant clustering in destinations when network effects are still likely to be small.

As emigration may continue over time, a "culture of migration" might emerge that changes a society's values and perceptions associated with migration (Massey et al., 1993). The culture of migration manifests at the individual level—people who have migrated in the past are more likely to migrate in the future—and the community level when migration becomes a normative behaviour—a "rite of passage"—in the community (Kandel & Massey, 2002). When information about migration options diffuses widely in the community, it can perpetuate migration. In a culture of migration, this information can also spread to people without direct access to migrant networks. The culture of migration, in contrast to network theory, can hence explain why people may migrate even in the absence of networks (Ali, 2007).

While the theories discussed so far have mostly focused on individuals or households as the decision-making unit, more structural theories conceptualise migration as an intrinsic part of historical processes and societal developments. Zelinsky (1971) argues that demographic transitions and modernisation processes explain the development and changing patterns of human mobility in Europe over the last 200 years. Historical-structural models, based upon neo-Marxist interpretations of capitalism, stress the importance of structures and forces operating at the macro-structural level. Migration is driven by the global demand and supply of cheap and flexible workers in segmented labour markets to sustain continued economic growth and development in capitalist labour-recruiting countries (Piore, 1979; Sassen, 1991). In the same way, world systems theory holds that capitalist systems destroy traditional economic structures and livelihoods, and thereby shape domestic and international migration patterns (Wallerstein, 1974). The world capitalist system, disguised in colonialism, has hereby triggered an 'age of migration' in the nineteenth and early twentieth century.

Contemporarily, in the postcolonial era, world systems theory claims that postcolonial systems resemble those during colonialism due to neoliberalism and corporate capitalism, including transnational ties (international trade, foreign investment etc.) between former colonial powers and colonies, but also a shared history and culture, language, administrative links, and migration governance (Fawcett, 1989). Historical-structural models have mainly been criticised for denying migrants' agency and regarding them "as little more than passive pawns in the play of great powers and world processes presided over by the logic of capital accumulation" (Arango, 2004, p. 27). Migration flows further do not always correspond to capital flows, as demonstrated by increasing South-South migration. These models also disregard the role of states, which political economy models of migration sought to rectify. Proponents of political economy models hold that political systems and geopolitical shifts in global economic, political, and military power drive migration processes (Castles, 2010; Czaika & de Haas, 2014).

#### 3.1.2 Migration Drivers: Dimensions and Functions

Migration theories establish multiple reasons of why, when, where, and how people migrate. They attribute different forms and levels of agency to individual migrants. While some theories point to specific factors that drive migration, others remain vague about the actual factors that drive migration. The circumstances, the ways and modes, and the extent to which a set of driving factors may influence migration (decision-making) processes are dependent on the functionality of migration drivers, which is a central aspect in understanding the specific role (single or combinations of) migration drivers may play in migration. What almost all migration theories have in common is that migration, as both an individual behavioural option and a broader collective action, is highly context-dependent. Consequently, the interplay of factors and configuration of complex driver environments the effect on migration outcomes is very specific to the time and space in which migration decisions are taken.

Context-specific functionalities of migration drivers can be distinguished along some key functions (cf. Van Hear et al., 2018). Predisposing factors reflect fundamental societal structures and structural disparities and define the broadest, most fundamental layer of opportunity structures (cf. de Haas, 2010). As a basic methodological premise, we may assume that people respond to extrinsic or intrinsic predisposing stimuli when deciding about migration (Czaika & Reinprecht, 2020). Predisposing factors do not directly, nor in an 'unfiltered' manner, affect people's decision-making but are mediated by drivers that facilitate, constrain, accelerate, consolidate, or diminish migration (Van Hear et al., 2018). For instance, structures of economic and social inequalities may be mediated by cultural norms (e.g. classbased, social status) or provisions of political and civil rights, which may absorb or neutralise the migration-stimulating effect of inequality structures. Similarly, drivers of immobility constrain migration and stimulate individuals to stay put (Schewel, 2019).

Proximate drivers 'downscale' and localise predisposing macro-structural factors bringing them closer to the immediate 'decision context' of a potential migrant. Macro-structure context and developments are disaggregated and translated into situational triggering factors of migration that establish the actual reasons for migrating, including unemployment, job offer, marriage, persecution, flooding, etc. Beyond the degree of immediacy, migration driver functions can further be characterised by their temporality, selectivity, and geography. Temporality refers to the permanent or transitory character of a driver. For instance, demographic transitions or adaptations of cultural norms are usually slow-changing and therefore relatively inelastic ('resilient') structural drivers while natural disasters, or a coup d'état, are phenomena resulting in rapidly changing driver environments ('shocks'). Selectivity refers to the fact that broader social, economic, or political transformations do not normally homogeneously affect all societal groups in the same way and to the same extent. Business cycles, for instance, can affect societal groups in very different ways and to an extent that depends on the age, gender, ethnicity, social status, or profession of the potential migrant. Finally, the geography refers to the locus and scope of a migration driver. The geographical scope of a macro-structural driver can be anything between local and global, while the locus of a migration driver refers to the geographical location of a migration journey where a driver may be operating (origin, transit or destination).

### 3.2 Migration Drivers: Interactions and Configurations

Migration is a decision taken in the context of personal needs, livelihood challenges and opportunities, stress, urgency and uncertainty, based on incomplete information about migration prospects and possible outcomes of alternative behavioural options. Thus, migration decisions are both situational and contextual, that is the configuration of complex driver environments is very specific to the time and place in which migration aspirations are formed and decisions taken. It is usually not a single driver but more often a complex combination of economic, political, social, and other developments and events that may dynamically influence both migration opportunities as well as the willingness and ability to migrate. The intertemporal accumulation of triggering factors leads to certain 'tipping point' situations, at which larger population movements are suddenly set in motion. For instance, many Syrians stayed in their hometowns years into the civil war and only fled to neighbouring countries once their economic basis of subsistence eroded and was further degrading through environmental stress to an extent where staying was no longer a viable option (Bijak & Czaika, 2020). Migration drivers may trigger, enable, mediate, or predispose an individual, a group of people, or a population to move. Migration drivers usually 'cluster to operate as more than the sum of the single drivers that constitute them' (Van Hear et al., 2018, p. 934). That is, migration drivers do not work in isolation but in combination with other migration drivers establishing migration driver configurations.

As we will see in the empirical part of this chapter, most studies analysing migration drivers only focus on very specific drivers of migration. Few studies explore complex configurations of drivers, including their often non-linear, interacting, and combined effects on migration processes. Interaction effects in particular are regularly neglected. They occur when the effect of one driver depends on the presence and intensity of one or more other factors. Interaction effects reflect the importance of third factors that may influence causal relationships between a driver of migration and migration outcomes.

#### 3.3 Migration Drivers: Some Empirical Evidence

#### 3.3.1 A Typology and Meta-review

Following the conceptualisation of migration drivers in the previous section, we now provide an overview of the existing evidence on the migration driver dimensions and factors and discuss the empirical state of knowledge. We synthesise evidence about migration processes more profoundly and hereby elaborate on key insights and

Table 3.1 Migration driver taxonomy: driver dimensions and driving factors

findings from the scientific literature across multiple domains of migration drivers.<sup>1</sup> To evaluate the driving factors of why people migrate, we consulted a vast amount of the empirical academic literature on migration drivers. The total number of studies of migration drivers has increased more than eightfold since 2010 with an average annual growth rate of over 12%.<sup>2</sup> In an attempt to structure this knowledge accumulation on the drivers of migration, we have developed a taxonomy consisting of nine driver dimensions and 24 driving factors that may all play a direct (independent) or indirect (conjoined) role in enabling or constraining migration processes at different analytical levels (Table 3.1). The dimensionality of migration drivers refers

<sup>1</sup> At this point, we acknowledge that the vast majority of the world's population never migrates, at least not internationally. While this may be partly due to the absence of one or a combination of the migration drivers reviewed in this study, there may also exist drivers of immobility (Schewel, 2019). However, we only review and synthesise existing knowledge of the circumstances under which people do, or intend to, migrate.

<sup>2</sup> This figure is based on a calculation of the total population of journal articles covering migration drivers in the IMISCOE Migration Research Hub (http://migrationresearch.com/) database since 2000.

to the nine societal areas a migration driver belongs to, each comprising a number of driving factors further specifying these broader dimensions. An extensive literature review has revealed that these 24 driving factors are not only priority areas of migration driver research but also play a key role for a more fundamental understanding of the dynamics of migration processes.

We identified driving factors both deductively through our and experts' knowledge of the migration literature, and inductively using a rapid evidence assessment (REA) of almost 300 empirical studies of migration drivers in 2019. The analysis builds on a rapid evidence assessment of this vast amount of scientific literature published until 2019.<sup>3</sup> We have not attempted to systematically assess the quality of the studies analysed but trust that collectively these studies are authoritative for understanding the role, effects, and functions of driving factors in migration processes. Figure 3.1 displays the share and distribution of reviewed empirical and non-empirical studies by driver dimension. On average, we identified 2.5 migration drivers per empirical study, which explains why the total number of drivers exceeds the total number of studies analysed (463). Economic and socio-cultural drivers hereby outnumber the other driver dimensions while environmental drivers have received relatively little attention. While this might reflect a biased selection of the literature, we believe that our extensive literature search is broadly representative of the core body of literature on migration drivers.

Figure 3.2 displays the distribution of the reviewed empirical studies according to driver dimension, method and level of analysis, locus of the migration driver, and data sources used. Almost half of all studies evaluate economic and socio-cultural