This book presents a historical study of the Roman Empire in Late Antiquity from the accession of the emperor Diocletian 284 to the death of the emperor Heraclius in 641. This is the only modern study to cover the western and eastern empire and the entire period from 284 to 641 in a single volume. A bibliographical survey supports further study and research. This work: includes chronological tables, maps, and charts of important information help to orient the reader; discusses the upheaval and change caused by the spread of Christianity and the barbarian invasions of the Huns, Goths and Franks; contains thematic coverage of the politics, religion, economy and society of the late Roman state; gives a full narrative of political and military events; and, discusses the sources for the period.