Demonologies are Comprehensive Tracts, written by learned men — physicians, jurists, and theologians — reviewing the history and theology as well as the legal and medical implications and consequences of the alleged interaction of humans with demons (fallen angels). They are, on the whole, an early modern literary genre, the rational exploration of a phenomenon that appears to the modern reader anything but rational. Over the two hundred years between Institoris’s (Heinrich Kramer, 1430–1505) Malleus maleficarum (The Witches’ Hammer) of 1487 and Johannes Praetorius’s (Hans Schultz, 1630–80) Des Blockes-Berges Verrichtung (Witches’ Sabbath on the Blocksberg) of 1668, numerous demonologies (or “witchcraft theories”) were published, read, and quoted in subsequent witch tracts, sermons, broadsheets, witch trials, and laws pertaining to the practice of witchcraft. According to Walter Stephens, witchcraft theory provided a way of systematically describing preexisting ideas about relations between humans and demons, the central source of evidence being the testimony of witches on trial.

Although the production and consumption of these texts was vigorous between the 1430s and the 1700s, twentieth-century historical and literary scholarship showed relatively little interest in them. In a critical assessment of the state of research on demonology as of 1977, it was found that, more often than not, demonologies had been neglected, or worse, rejected as aberrant musings of otherwise reasonable men; analysis of the structure, arguments, language, interrelations, and reception of these texts had been dismissed as unessential and uninteresting. Critics had focused on nontextual realities in society, including legal practices in local communities, rather than examining the pertinent texts. A reader of the research of the nineteenth and a good part of the twentieth century could not have readily determined that demonologies were central to the times in which they were produced or that they had been frequently translated and cited as authoritative sources on an issue of great interest to learned and lay audiences. During the early modern period demonology and its counterpart angelology, the study of angels, constituted a fundamental aspect of Christian cosmology and thus were integral to contemporary theology and science. The majority of scholars in the early modern period, no matter what their professional specialization and whether they supported or opposed the persecution of witches, accepted as basic the premise that demons and witches existed and that they could and did harm humankind.