German-speaking lands in the twelfth and thirteenth centuries were home to the largest Jewish communities north of the Alps and Pyrenees and thus constituted key locations for Christian-Jewish interaction. This dissertation examines the monasteries of Germany' the primary centers of intellectual and cultural production in the high medieval Empire' as loci for that interaction. It explores both the social/economic and the cultural aspect of contact between monks and Jews. In the process, it challenges traditional interpretations of Christian-Jewish relations and helps to fill in the picture of the lives and activities of monks in this period. The study proceeds in three parts. Part one, comprising the first three chapters, examines the political context wherein Jews and monks interacted before investigating evidence of contact between Jews and monks in the social and economic spheres. This evidence demonstrates that Jewish communities and monasteries occupied similar political positions in this society' due to their mutual reliance on the institution of privilege' and that they engaged frequently in business dealings with each other. Part two (chapters 4-6) turns its attention to the intellectual and cultural realm, examining ideas about Jews that circulated in the monasteries. While monks obtained many of these ideas from patristic works and other earlier sources, they actively developed and modified these ideas in ways that spoke to contemporary concerns. The last part, consisting of the final chapter, examines the issue of Jewish conversion to Christianity. This issue, perhaps better than any other, forced monks to deal with both real Jews and cultural constructions of Jews. This dissertation contends that the definitive attribute of monastic-Jewish interaction in this period was ambivalence. Real interactions were quite normal, even friendly, yet the ideas about Jews that monks developed were largely, though with some important exceptions, hostile. Such a characterization calls into question prevalent explanations of Jewish-Christian interaction, which tend to emphasize escalating hostility and uniformity ideas across regions and institutions.