Count Marcellinus and his Chronicle constitutes the first comprehensive study of Marcellinus, a courtier of the emperor Justinian, and his chronicle covering the eastern Roman world from AD 379 to 534. Marcellinus' chronicle provides a first-hand account of the Nika riots at Constantinople in 532, as well as other direct glimpses of political and religious life in the imperial capital in the early sixth century. It also testifies to the confrontations in the Balkans between the Romans and the Huns, Goths, and Bulgars.

In this book Brian Croke develops a case for understanding Marcellinus' Latin chronicle as an essentially Byzantine document written by an educated imperial official and reflecting the cosmopolitan culture and society of sixth-century Constantinople. He approaches the chronicle as a historiographical text which is shaped by its genre, the expectations of its audience, and a coherent view of the past, deriving from the author's Christian culture and outlook. The book also explores the nature and function of chronicle writing as a distinct mode of Christian discourse which has been misunderstood and undervalued by modern scholarship. Separate attention is given to the anonymous continuation of the chronicle from 535 to 548, and to the subsequent use of Marcellinus' works in Ireland and Anglo-Saxon England.

Croke also casts new light on the career of Marcellinus, his range of literary output which included books on topography and chronology, and the course and impact of the fifth- and sixth-century raids into Roman Illyricum. This book also enriches our understanding of society and politics in the imperial capital and raises broader questions about Christian life, liturgy, and culture in the sixth century, particularly the central role of imperial and religious ceremonial in Byzantine public life.