There are many reasons for returning to a field in which I was involved twenty years ago, when I brought out a detailed analysis of the Nika riot. Given the theme of this volume, however, it would be of little relevance to focus too narrowly on the events of January 532.1 Instead, I propose to examine at a more general level the dynamics of riots in the fifth and sixth centuries, seeking in particular to discern what factors were involved, and more particularly to what extent religious or doctrinal loyalties played a part, and what the consequences of the developments over this period were. I shall start with a brief survey of how approaches to factions and violence have changed in recent scholarship; one of the key themes here will be the blurring of lines between factional and religious violence, as scholars have underlined the numerous common traits of factions and the Church, both of which constituted powerful empire-wide organisations with their own objectives and interests.2