We often associate the passage from the classical period to the post-classical with the rise of Christianity. Over the long centuries during which Christianity expanded from its Abrahamic origins in Mediterranean Judaism, its influence was impressed upon the urban landscape, political ceremonial, the orientation of the intellectual culture and artistic aesthetics, expressions of communal identity and personal piety, definitions for the family and the “marginal” in society and even the mental structures by which people thought about the past. As a result, the rise of Christianity has saturated the evidentiary fabric by which modern readers of the past construct the caesura between the classical world and its post-classical successors. The role played by Constantine as the first Christian emperor of the Roman Empire naturally has also profoundly shaped the manner in which we frame Late Antiquity and successive periods. Indeed, the modern demarcation of the post-classical period is often inseparable from the reign of Constantine. Survey studies of Late Antiquity and the Middle Ages typically commence with Constantine’s reign (or that of Diocletian, as a means of foregrounding the “Constantinian revolution”).