The Conclusions explore the consequences of our arguments for the study of late antiquity more generally and the patterns of Roman military organization. The Roman military was among the most important institutions in the ancient world, and revising its history has ramifications for such perennial questions as imperial decision-making and Roman identity. Moreover, our reconstruction creates new questions, in particular about the economy of the fifth-century east Roman empire and its ability to mobilize and sustain the armies described by the Notitia. This chapter concludes by situating our revised narrative within the longe durée of Roman military history from Augustus to Byzantium and identifying the major considerations, including many non-military considerations, that motivated the empire’s various military configurations.

This chapter argues that the military and political history and prosopography of the early fifth century cannot be reconciled with the existence of the Notitia system. Specifically, the military challenges the east Roman empire faced during this period, most notably Alaric’s depredations in the Balkans, Gaïnas’ revolt in Asia Minor, and attempts to prop up the struggling western empire, all point to a systemic under-militarization in the east that forced Constantinople to rely heavily on barbarian manpower, often with calamitous results. By the 420s, we find evidence for a gradual remilitarization taking place in the east, which set the stage for the major reforms of the 440s.

This chapter surveys the organization of the east Roman military from the failure of Julian’s Persian expedition to the death of Theodosius I in 395. It demonstrates that there is no evidence to support the emergence of the Notitia system during this period and, in fact, positive evidence indicating that the Roman military continued to operate in its fourth-century configuration, with a central reserve army, the comitatus, commanded by a magister equitum and magister peditum, while smaller regional commands were managed by local limitanei or, in exceptional cases, a comes rei militaris. The sole exception was the magister militum per Orientem, the chief general on the eastern frontier, whose office went from an ad hoc appointment to a formally constituted command during this period.

This chapter traces the gradual unwinding of the Notitia system in response to the shifting strategic needs of the east Roman empire. Anastasius began the process by deploying the praesental armies to the east, first against the Isaurians and then against the Persians, but it was Justinian who fully dismantled them. Beginning with his creation of a new military command for Armenia and continuing through the establishment of a standing field army for North Africa and Italy, Justinain cannibalized the praesental armies and dispersed the striking power of the armies of Oriens, Thrace, and Illyricum. The consequences of Justinian’s decisions were keenly felt by his successors who struggled to defend the empire against escalating threats in the Balkans and the east. By the time Herakleios came to the throne, the Romans could barely muster three field armies, those for Thrace, Armenia, and Oriens, and it was these depleted armies that Herakleios used to defeat Persia and lay the basis for the thematic armies of Byzantium.

This chapter demonstrates that all of the available evidence indicates that the Notitia system was rapidly put into place in the 440s, likely in response to the invasions of Attila the Hun on the Danubian border. Although designed to face down the threat of the Huns, the system continued to operate as the collapse of Attila’s kingdom put increasing pressure on the eastern empire, in particular in the form of Theoderic Strabo and Theoderic the Amal, two Gothic warlords who repeatedly ravaged the Balkans and assaulted Constantinople during this period. Placed in its proper context, many central features of the Notitia system become intelligible, in particular its strong Balkan focus and the function of the praesental armies, which were used as reserve forces.

This chapter discusses responses to Thucydides’ History in the thousand-year period between the foundation of Constantinople in 330 CE and the appearance of the first translations of Thucydides in the late 14th century. The chapter describes the processes by which the text was preserved and transmitted and how it was read and understood in this period. It also explores the question of why the Byzantines were interested in Thucydides and the creative ways in which some Byzantine authors adapted or redeployed Thucydides’ work in their own writing.

Chapter 3, “The People of Constantinople,” tracks population numbers across the centuries together with the factors that contributed to growth and decline. It also examines the ethnic and demographic make-up of the capital’s population.