John Pfefferkorn (1469-1522), born a Jew and converted to Christianity (1505), animated with the zeal of a convert to bring the Jews wholesale to Christianity, and perhaps stimulated by the Dominicans of Köln (Cologne), with whom he was closely associated, conceived an idea that his former co-religionists might be induced to accept Christianity if all their peculiar books, the Old Testament excepted, were confiscated. During the earlier Middle Ages the Jews had been continually persecuted, and their persecution had always been popular; but the fifteenth century had been a period of comparative rest for them; they had bought the imperial protection, and their services as physicians had been gratefully recognised in Frankfurt and many other cities.(42) Still the popular hatred against them as usurers remained, and manifested itself in every time of social upheaval. It was always easy to arouse the slumbering antipathy. Pfefferkorn had written four books against the Jews (_Judenspiegel_, _Judenbeichte_, _Osternbuch_, _Jeudenfeind_) in the years 1507-1509, in which he had suggested that the Jews should be forbidden to practise usury, that they should be compelled to listen to sermons, and that their Hebrew books should be confiscated. He actually got a mandate from the Emperor Maximilian, probably through some corrupt secretary, empowering him to seize upon all such books. He began his work in the Rhineland, and had already confiscated the books of many Jews, when, in the summer of 1509, he came to Reuchlin and requested his aid. The scholar not only refused, but pointed out some irregularities in the imperial mandate. The doubtful legality of the imperial order had also attracted the attention of Uriel, the Archbishop of Mainz, who forbade his clergy from rendering Pfefferkorn any assistance.