A study of the 12th-century evolution of innovative anti-Jewish stereotypes and their impact on subsequent Western thought. The 12th century was a period of significant change and dislocation in the West; it witnessed the interaction of new societal circumstances and a prior ideational legacy, similar to events in the 19th-20th centuries. This interaction produced an innovative view of Jews which was fated to influence anti-Jewish perceptions up to the present. In the period of societal change, persecutory patterns emerged, directed at diverse societal outgroups, among them the Jews. The 12th-century stereotypes were permanently absorbed into the historic legacy of Christian anti-Jewish thinking. These stereotypes were based on a perception of Jewish hatred of Christianity and Christians, and that Jews commit acts of anti-Christian violence generated by this purported hatred (e.g. ritual murder, abuse of Christian symbols, moneylending abuses). The most pernicious anti-Jewish imagery involves stereotypes alleging mortal threats posed by Jews. States that every new stage in the evolution of anti-Jewish thinking is marked by dialectical interplay between a prior legacy of negative stereotypes and the realities of a new social context.