“Anthropophagy in Three Keys: New World Cannibalism, the Blood Libel, and Corpse Medicine in the British Atlantic World, 1640-1660” investigates the English responses to alleged Jewish and Indigenous anthropophagy in the mid-seventeenth century and contrasts them with the practice of medicinal cannibalism, which became widespread in Interregnum England. This thesis argues that cannibalism was used to distinguish in-group from out-group as anxieties around the literal and metaphorical consumption of human bodies resonated in both English metropole and New English colony. These anxieties were made manifest in concerns about territorial expansion, eschatology, and scientific and medical practice; they culminated in persistent, self-aware hypocrisy by English corpse medicine practitioners who were also deeply involved in colonizing efforts and the debate surrounding the possible readmission of Jews to England. Furthermore, “Anthropophagy in Three Keys” reveals the utility of cannibalism as an analytic tool for seventeenth-century Atlantic World history.