Almansor’s death weakened the Ommiade dynasty, and Cordova fell a prey to discord; in place of one strong ruler now were many petty chiefs, each one anxious to make himself supreme, but only succeeding in adding to the confusion then prevailing among the Moors. Before the middle of the century the crowns of Leon and Castile had been united under Ferdinand the Great, and in the year 1082 his son and successor, Alfonso VI, went down and besieged the ancient city of Toledo (which had been in Moorish possession four hundred years), taking it three years later. It was never recovered by the Moors, and the Moslems became alarmed at this signal instance of Gothic bravery and effrontery, and for a time ceased their dissensions. But, in their alarm at the aggressions of the Christian forces, they placed their necks within a yoke of slavery far worse than would have been forced upon them by the Goths. They conferred together, and, realizing their own weakness, sent over into Africa for assistance. There then reigned in Morocco the fierce Yussef, a fanatical Bedouin, who hated all Arabs almost as much as he hated the “Christian dogs.” But he hastened to the relief of his fellow–Moslems with a great army of fanatics as fierce and uncouth as himself. He had hardly landed and learned of the fall of Toledo, when he summoned King Alfonso either to embrace the faith of Mohammed, consent to pay tribute, or prepare for battle. Flushed with his successes, Alfonso chose to fight, and the two great armies met in the battle of Zallaca, in the month of October, 1086, when the Spanish army was utterly overthrown. Yussef pursued his advantage vigorously, and eventually all southern Spain was subjected to him, including the city of Seville, which was taken in 1091; and not only were the Christians themselves the object of his fury, but the Moslem chiefs who had sent for him to come to their aid, who were all either murdered or transported to Africa. Thus was the Almoravid dynasty established, with its capital at Cordova, and which lasted until 1147. Yussef died about twenty years later, leaving the kingdom to his son Ali, and the Spanish Moslems were oppressed by the Bedouin chiefs, who were as savage and illiterate as the Ommiades were gentle and refined. Cordova soon lost its libraries, its schools and universities, and became a place to be shunned, rather than sought, by scholars and men of letters.