The name of the false prophet was omitted from the prayer in the mosques. His title was erased from the inscriptions of the coinage. All magistrates were prohibited from alluding to him in their decisions. These measures, adopted in defiance of public sentiment, were not conducive to the permanence of usurpation. The memory of the Mahdi was still revered by the illiterate and fanatical masses of Africa. In all ages sacrilege has been the most dangerous offence of which a monarch could be guilty; and after these impolitic exhibitions of jealousy nothing but the ferocious character of their sovereign deterred the exasperated Berbers from rebellion. While Al-Mamun was strengthening his empire in Africa, his influence was rapidly declining in Spain. A new antagonist, well worthy to assert, in an age of national decadence, the rights of an outraged people, had arisen as the representative of Andalusian liberty. Mohammed-Ibn-Hud, who concealed under the mask of patriotism an ambition which aimed at despotic power, stood forth as the champion of the oppressed. His extraction was noble,--he was a lineal descendant of the famous dynasty of Saragossa; but no royal ancestry was required to dignify a character eminent for military genius, political sagacity, and the exercise of every princely virtue. Influential chieftains at once ranged themselves around him. His increasing power enabled him to seize and retain the Emirate of Murcia. His cause was promoted by the assurance that all taxes imposed by Almohade tyranny would be abolished, and that the Africans would be either expelled or exterminated. These pledges were speedily fulfilled. An overwhelming proportion of the inhabitants of Moorish Spain supported the claims of the alleged representative of freedom. The doctrines introduced by the Mahdi were declared schismatical, and his disciples branded as public enemies. The mosques in which their rites had been celebrated for more than a century were cleansed and rededicated with the same solicitude and ceremony as would have been displayed in the purification of Pagan temples. Those of the hostile faction who had made themselves offensively conspicuous were promptly executed; the less obnoxious were exiled. White, the official color of the followers of the Mahdi, was superseded by black, the distinguishing badge of the Abbasides; for Ibn-Hud had already publicly announced his allegiance to the khalifs of Bagdad. The revolution soon spread to the confines of the Moslem territory. The Arabs and the Andalusians avenged the accumulated evils of generations by the butchery of every African who fell into their hands. The emirs of Granada and Valencia were expelled by the exasperated populace. Al-Mamun, having undertaken to suppress the rebellion, sustained a decisive defeat at Tarifa, and the prestige of Ibn-Hud, increased by this fortunate event, now became greater than ever.