BY the early thirteenth century, the situation of European Jewry had become a precarious one. No longer considered a separate genus with well-defined rights, legally and constitutionally, the Jews had become directly dependent on feudal suzerains and were prey to arbitrary rule. Their mode of earning a living, largely through lending at interest (in northern Europe, at any rate), was viewed with general suspicion and disdain. Their affective nuclear family ideal and structure, wholly sustained by Jewish religious and political leadership alike, often seemed — and was — foreign to that of their Christian neighbours, and certainly to the ideal sustained by Christian clerics. Finally, their image in Christian eyes had universally become that of the nemesis of the Christian polity. They were alternately viewed as the personification — and, by projection, the incarnation — of perverse, unhuman, reason and reasoning; as the object on which to project and transfer irrational doubts and frightening convictions, most notably the conviction of the real presence of Christ in the Eucharist; and as the foil for promoting, conjointly with theories of worldwide conspiracies, the Marian cult and other local cults of saints, often in association with libels of ritual murder. Any, or all, of these views was sufficient to generate an image of the Jew as a mythical threat to Christian society. As the source, first, of spiritual pollution, then of the corruption of the Christian body politic, and eventually, in the sixteenth century, if not earlier, of pollution by infection of the physical and individual Christian body itself, occasionally accompanied by charges of magic, although pointedly not of witchcraft, the Jew was deemed capable of subverting a Christian society’s legitimate aims and goals. Since 1096, during the First Crusade, such conclusions increasingly exposed the Jews to libel and physical attack. What role, we can now ask, did the institution of the Catholic Church, its leaders and their ideologies play in either fomenting or moderating this state of affairs?