One of these missionaries, disguised as a merchant, journeyed back to Barbary in 893, with some Berber pilgrims who had performed the sacred ceremonies at Mecca. He was welcomed by the great tribe of the Kitama, and rapidly acquired an extraordinary influence over the Berbers--a race prone to superstition, and easily impressed by the mysterious rites of initiation and the emotional doctrines of the propagandist, the wrongs of the prophetic house, and the approaching triumph of the Mahdi. Barbary had never been much attached to the caliphate, and for a century it had been practically independent under the Aglabite dynasty, the barbarous excesses of whose later sovereigns had alienated their subjects. Alides, moreover, had established themselves, in the dynasty of the Idrisides, in Morocco since the end of the eighth century. The land was in every respect ripe for revolution, and the success of Abu-Abdallah esh-Shii, the new missionary, was extraordinarily rapid. In a few years he had a following of two hundred thousand armed men, and after a series of battles he drove Ziyadat-Allah, the last Aglabite prince, out of the country in 908. The missionary then proclaimed the imam Obeid-Allah as the true caliph and spiritual head of Islam. Whether this Obeid-Allah was really a descendant of Ali or not, he had been carefully prepared for the role, and reached Barbary in disguise, with the greatest mystery and some difficulty, pursued by the suspicions of the Bagdad caliph, who, in great alarm, sent repeated orders for his arrest. Indeed, the victorious missionary had to rescue his spiritual chief from a sordid prison at Sigilmasa. Then humbly prostrating himself before him, he hailed him as the expected mahdi, and in January, 910, he was duly prayed for in the mosque of Kayrawan as "the Imam 'Obeid-Allah el-Mahdi, Commander of the Faithful.'" The missionary's Berber proselytes were too numerous to encourage resistance, and the few who indulged the luxury of conscientious scruples were killed or imprisoned. El-Mahdi, indeed, appeared so secure in power that he excited the jealousy of his discoverer. Abu-Abdallah, the missionary, now found himself nobody, where a month before he had been supreme. The Fatimite restoration was to him only a means to an end; he had used Obeid-Allah's title as an engine of revolution, intending to proceed to the furthest lengths of his philosophy, to a complete social and political anarchy, the destruction of Islam, community of lands and women, and all the delight of unshackled license. Instead of this, his creature had absorbed his power, and all such designs were made void. He began to hatch treason and to hint doubts as to the genuineness of the Mahdi, who, as he truly represented, according to prophecy, ought to work miracles and show other proofs of his divine mission. People began to ask for a "sign." In reply, the Mahdi had the missionary murdered.