In the mean time, after the capture of Almeria, the Christians began again to exert their power in every Moslem province of the Peninsula. The Count of Barcelona, supported by the Italian fleets, invested and took Tortosa, which commanded the mouth of the Ebro. Its submission was followed by the conquest of Lerida, Fraga, and Mequinenza, and the great river of Aragon, now open to the sea, marked for a brief period the gradually contracting boundary of the Moorish possessions of Eastern Spain. The rising monarchy of Portugal, for the first time beginning to assert itself among nations, acquired renewed prestige by the capture of Cintra and Lisbon. The movements of Ibn-Gamia, whose valor and activity still sustained the sinking fortunes of the Almoravide cause, stimulated the Almohades to exertion. Worsted in several encounters, he retired to Cordova, but, unable to maintain his ground, he placed his lieutenant Yahya in command and effected a retreat by night after the Almohades had encamped before the city. Yahya, by a prompt submission, averted the carnage which in these wars inevitably followed a protracted defence, and the ancient metropolis of the khalifate once more submitted to the rule of a foreign master. In the Great Mosque, the scene of so many triumphs and humiliations, which had witnessed the installation of a long succession of Moslem princes, the public exhibition of the trophies of conquest, the murder of magistrates, the tumults of revolution, Abd-al-Mumen was proclaimed Emir of the Mussulmans of Spain. The fierce spirit of the invaders seems to have been restrained by the dangers of the situation, the uncertainty of support, and the activity of the Christians, considerations which rendered leniency towards the vanquished not only politic but necessary. Carmona was soon added to the Almohade conquests and Ibn-Gamia fled to Granada, where he afterwards fell in battle. His partisans then espoused in a body the cause of Alfonso of Castile. With this open defection the condition of the Spanish Moslems became more desperate. Divided among themselves, with half of their best soldiers fighting under the banners of their hereditary foe, apparently abandoned by the prince raised to imperial power in the religious centre of the kingdom, without resources, without prospect of assistance, nothing but the presence of the Almohades preserved the relics of the khalifate from immediate absorption by the kingdoms of Castile and Aragon. Finally, Abd-al-Mumen, having consolidated his empire in Africa, and moved by the entreaties of his Andalusian subjects, who sent a deputation of five hundred citizens to invoke his aid, despatched an army under his son Abu-Said to the Peninsula. The city of Almeria, whose situation, in a strategic point of view, commanded the coast of Africa, was the object of the expedition. The siege having been formed, an ineffectual attempt was made by Alfonso