The study of travel in Late Antiquity is complicated by a specific set of factors that will appear throughout this volume and in every period: namely, the motivations and goals of the travellers. This is especially true in Late Antiquity because the mental shape of the world was changing quickly and dramatically from what came before. The imperial reign of Constantine (306–337) ushered in for Christian writers a long-expected saeculum of imperial peace and the triumph of the Christian message. The motivations for travel in Late Antiquity very often can only be read on the background of that paradigm shift. The triumph of the Church was inextricably linked to the shape of the empire, notionally and geographically. That same empire in which Christians formerly had moved quietly and in secret was now an open space for travel and expansive thinking. Thus, travel in Late Antiquity went hand-in-hand with new geographical horizons: not primarily a physical expansion of “the known world” (the oikoumenē in Greek), though that came too, but a freedom of expression through movement within the Roman Empire they already knew.