Witches, ghosts, fairies. Late medieval and early modern Europe was seemingly filled with these and other threatening and disturbing figures. For many contemporary authors, the devil appeared to lurk behind them all. Were his powers real or mere trickery? What limits did God place on them? Could reports from this hidden demonic netherworld be trusted? Physicians, lawyers, and theologians, writing at different times and places, gave very different answers and often disagreed bitterly. This updated and enlarged second edition examines individual authors from across Europe and its colonies to reveal the many purposes to which the devil could be put – in the late medieval fight against heresy, the age of Reformations, and beyond. It follows the devil’s trajectory from his emergence in the 1300s and 1400s as a bodily figure who made pacts with humans, through the comprehensive surveys that coincided with the witch-hunts’ most deadly phase, to the end of the seventeenth century, when the science of demons met new challenges in both Old World and New. This book is essential reading for students, researchers, and anyone interested in the history of the supernatural in medieval and early modern Europe, as well as those exploring the intersections of theology, science, and society during this transformative period.