The Movement of People: Exiles and Slaves in Byzantine and English Treaties

The movement of people is a stable of modern treaties, and was also a common issue in the treaties of the medieval world. Whether dealing with the emir of Aleppo or the prince of Gwynedd, rulers consistently collaborated to control the movement of people, and in particular the movement of slaves and exiles. While there is scholarship on this issue, relatively little work has approached this issue within the treaties. As treaties reflect how polities saw a shared problem and a shared solution, they provide the best evidence for studying diplomacy and its connection to surrounding laws and customs, and give insight into the legislative infrastructure that rulers utilised to approach this issue. In this paper, I will show how and why rulers were diplomatically active in dealing with both slaves and exiles. To do this, I have analysed treaties from two of the most bureaucratic powers of the medieval world, Byzantium and England, ensuring there is ample material for analysis. This will highlight that both the kings of England and the emperors of Byzantium were proactive in controlling the movement of slaves and exiles, which was an essential requirement for peace in their own realm as well as that of their neighbours.