Published in 1516, Poul Ræff's "Iudeorum Secreta", a translation of Johannes Pfefferkorn's The Confession of the Jews, was a landmark in the development of anti-Jewish polemics in Denmark. For the first time, Danes were presented with descriptions of Jewish ceremonies that aimed to portray these practices as dangerously anti-Christian, superstitious and deviating from 'real' Biblical Judaism. Contemporary Judaism is described as a rabbinical construction that is worthy of nothing but ridicule and mockery. The book explores this key text that comprises a valuable source for a range of academic disciplines: the history of anti-semitism, the study of Jewish-Christian relations, social history, the history of religious culture, and medieval and early modern Danish language and literature. This book includes an outline of how Jews were portrayed in medieval Danish vernacular literature; a description of Pfefferkorn's life and works; a discussion of Ræff's translation and publication of Iudeorum Secreta; a presentation of the language and style of the Danish version, as well as an edition of the text together with the Latin original, an English translation and an extensive commentary.