The school that had been founded by Gershom in Mayence flourished for more than eighty years, and became the center of Talmudic activity for Germany, France and Italy. At the same time, about the end of the fourth century of the Hejira, when the Karaites expected the coming of the Messiah, persecution broke out against the Jews in the East and in Egypt, and lasted longer than that in Germany. The German Jews had been persecuted because they did not believe in Christ and the saints; the Eastern Jews were now oppressed because they would not believe in Mahomet and the immaculate Imam, in the heavenly guide (Mahdi). This persecution was originated by the mad Egyptian Caliph Hakim, a Mahometan Caius Caligula, who believed that he was the incarnation of the divine power, and the vicegerent of God on earth. Hakim persecuted all who dared doubt his divinity--Mahometans, Jews, and Christians, without distinction. At first he decreed that if the Jews of his dominion did not become converts to the Shiitic Islam, they would have to wear round their necks the picture of a calf in commemoration of the golden calf of their ancestors in the wilderness. In addition, they were to be distinguished from the believers by their external appearance, as ordained by Omar. Those who transgressed were to be punished by exile, and by the loss of all their possessions (1008). A similar regulation was enacted against the Christians. When Hakim heard that the Jews evaded his decree by wearing a golden image of a calf, he added a further clause, viz., that they should wear in addition a block of wood six pounds in weight, and have little bells attached to their garments that they might be known at a distance as unbelievers (1010). He afterwards ordered the churches and synagogues to be destroyed, and drove both Jews and Christians out of his kingdom (1014). The Fatimide dominions at that time were very extensive. They embraced Egypt, northern Africa, Palestine and Syria, and since Hakim had adherents also in the Caliphate of Bagdad, there were but few places of refuge open to the Jews. Many, therefore, outwardly conformed to Islam, while waiting for better times to come. The persecution lasted till the Mahometans themselves grew tired of the half-witted Caliph, and assassinated him (1020).