First published in two volumes in 1879, Demonology and Devil-Lore is Moncure Daniel Conway’s wide-ranging attempt to trace the development of demons and devils through mythology, folklore and religious history. Written during a period of growing European interest in comparative mythology and the historical study of religion, it approaches supernatural traditions not simply as collections of strange beliefs, but as evidence of how different societies attempted to explain danger, suffering and evil.

Conway begins by considering the origins and classification of demons. He argues that many demonic figures developed as personifications of the forces and conditions that threatened human life. Separate chapters examine demons associated with hunger, heat, cold, storms and other elements, animals, enemies, barrenness, obstacles, illusion, darkness, disease and death. His discussion ranges across traditions from India, Persia, Egypt, Europe and elsewhere, bringing together figures including Loki, Beelzebub, Kali, Yama, Asmodeus and numerous dragons, serpents, spirits and monsters.

The work then turns to the transformation of these figures over time. Conway considers how the gods of one culture could become the demons of another, particularly through religious conflict and cultural change. His extended treatment of serpent and dragon traditions examines figures such as Apophis and the basilisk alongside legends of dragon-slayers and supernatural combat.

In the later sections, Conway distinguishes the more varied figure of the demon from the increasingly concentrated idea of the Devil. He examines Satan, diabolism, temptation, hell, witchcraft and the ways Christian traditions absorbed or reinterpreted earlier supernatural figures. The original work also contains numerous illustrations drawn from artistic, archaeological and religious sources.

Conway’s comparative method and some of his assumptions about the development of religion belong firmly to nineteenth-century scholarship and should not be treated as present-day academic consensus. The book nevertheless remains a substantial historical document in the study of demonology, mythology and comparative religion, showing how a Victorian freethinker attempted to explain the changing forms given to evil across cultures.