From his lifetime, much of Durkheim's work would be concerned with how societies could maintain their integrity and coherence in modernity, an era in which traditional social and religious ties are no longer assumed, and in which new social institutions have come into being. His first major sociological work would be (1893; "The Division of Labour in Society"), followed in 1895 by ("The Rules of Sociological Method"), the same year in which Durkheim would set up the first European department of sociology and become France's first professor of sociology. Durkheim's seminal monograph, "Le Suicide" (1897), a study of suicide rates in Catholic and Protestant populations, especially pioneered modern social research, serving to distinguish social science from psychology and political philosophy. The following year, in 1898, he established the journal "L'Année Sociologique". (1912; "The Elementary Forms of the Religious Life") presented a theory of religion, comparing the social and cultural lives of aboriginal and modern societies.