Yusuf [says Burke] had come as a Moslem defender, but he remained as a Moslem master. And once more in Spanish history, the over-powerful ally turned his victorious arms against those who had welcomed him to their shores. Yet Yusuf was no vulgar traitor. He had sworn to the envoys of the Spanish Moslems that he would return to Africa, in the event of victory, without the annexation to his African empire of a field or a city to the north of the Straits. And his vow was religiously kept. Retiring empty-handed to Mauritania, after the great battle at Zalaca, he returned once more to Spain, unfettered on this new expedition by any vow, and set to work with his usual vigor to make himself master of the Peninsula. Tarifa fell in December. The next year saw the capture of Seville, and of all of the principal cities of Andalusia. An army sent by Alfonso VI., under his famous captain, Alvar Fanez, was completely defeated, and all Southern Spain lay at the feet of the Berber, save only Valencia, which remained impregnable so long as the Cid lived to direct the defense. In 1102, after the hero’s death, Valencia succumbed, and all Spain to the south of the Tagus became a province of the great African empire of the Almoravides. The rule of these hardy bigots was entirely unlike that of the Ommeyad Caliphs of the West. Moslem Spain had no longer even an independent existence. The sovereign resided not at Cordova, but at Morocco. The poets and musicians were banished from court. The beauties of Az Zahra were forgotten. Jews and Christians were alike persecuted. The kingdom was governed with an iron hand. But if the rule of the stranger was not generous, it was just, and for the moment it possessed the crowning merit that it was efficient. The laws were once more respected. The people once more dreamed of wealth and happiness. But it was little more than a dream. On the death of Yusuf in 1107 the scepter passed into the hands of his son Ali, a more sympathetic but a far less powerful ruler. In 1118 the great city of Saragossa, the last bulwark of Islam in the north of the Peninsula, was taken by Alfonso I. of Aragon, who carried his victorious arms into Southern Spain, and fulfilled a rash vow by eating a dinner of fresh fish on the coast of Granada. Yet it was by no Christian hand that the empire of the Almoravides was to be overthrown.