section_path: Later Roman Empire
section_name: Later Roman Empire
paragraph_text: Later Roman Empire
  
  The Roman Empire reached its greatest territorial extent during the 2nd century AD, and the following two centuries saw the slow decline of Roman control of its outlying territories. Runaway inflation, external pressure on the frontiers, and outbreaks of plague combined to create the Crisis of the Third Century. The army doubled in size and military expenses steadily increased, primarily in response to the war with the Sasanian Empire. The need for revenue led to increased taxes, more centralised and bureaucratic state administration, and a decline in numbers of the curial (landowning) class. Emperor Diocletian (r. 284–305) split the empire into separately-administered eastern and western halves in 286. This system, which eventually had two senior and two junior co-emperors (known as the Tetrarchy) stabilised the imperial government for about two decades. After a period of civil war, Constantine the Great restored internal peace and re-founded the city of Byzantium as the eastern capital of Constantinople in 330.
  
  Roman society stabilised in a new form which differed from the earlier classical period, with a widening gulf between rich and poor and a decline in the vitality of smaller towns. Another change was the Christianisation of the Roman Empire accelerated by the conversion of Constantine, although Christianity emerged as the empire's dominant religion only at the end of the 4th century. Debates about Christian theology intensified, and those who persisted with theological views condemned at the ecumenical councils faced persecution. Heretical views survived through proselytising campaigns outside the empire or because of local ethnic-group support; examples include Arianism among the Germanic peoples and monophysitism in Egypt and Syria. Judaism remained tolerated, although legislation limited Jewish rights.
  
  The early Christians developed their own symbolism by the 3rd century, often by reinterpreting popular motifs of pagan Roman art. The solemnity of later Roman artists' abstract style effectively visualised Christian messages, and Christ's enthroned figure became a principal element of early Christian art. Under Constantine, basilicas (large halls which had been used for administrative and commercial purposes) were adapted for Christian worship. The first illuminated manuscripts —hand-written books decorated with colourful miniatures—were produced with the spread of silent reading in the 5th century.
  
  Civil wars between rival emperors diverted soldiers from the empire's frontier forces, allowing invaders to encroach beginning in the mid- 4th century. Although these movements of peoples have been described as "invasions", they were often not just military expeditions but mass migrations into the empire. In 376, hundreds of thousands of Goths fleeing from the Huns received permission from Emperor Valens (r. 364–78) to settle in Roman territory in the Balkans. The settlement did not go smoothly and, when Roman officials mishandled the situation, the Goths began to raid and plunder. Valens, attempting to put down the disorder, was killed fighting the Goths at the Battle of Adrianople. The Alans, Vandals, and Suebi crossed into Gaul in 406, and into present-day Spain in 409; a year later, the Visigoths (a Gothic group) sacked the city of Rome. The Franks, Alemanni, and the Burgundians ended up in Gaul; the Germanic groups now collectively known as Anglo-Saxons settled in Britain, and the Vandals conquered the province of Africa. The Hunnic king Attila (r. 434–53) led invasions into the Balkans in 442 and 447, Gaul in 451 and Italy in 452, but his Hunnic confederation fell apart after his death.
  
  To deal with the migrations, the Eastern Roman elites combined the deployment of armed forces with gifts and grants of offices to the tribal leaders; the Western aristocrats failed to support the army and refused to pay tribute to prevent invasions by the tribes. These invasions led to the division of the western part of the empire into smaller political units, ruled by the invading tribes. The 5th-century emperors were often controlled by military strongmen such as Stilicho (d. 408), Aetius (d. 454), Ricimer (d. 472), or Odoacer (d. 493), who were partly (or fully) non-Roman. Odoacer deposed Romulus Augustulus (r. 475–76), the last western emperor, assumed the title of rex (king) and took full control of Italy, although in theory he ruled as a representative of the eastern emperor Zeno (r. 474–91). The Eastern Roman Empire (known as the Byzantine Empire after the fall of its western counterpart) had little ability to control the lost western territories, but its emperors maintained a claim on them.