3 02 THE HISTORY OF MEDIEVAL EUROPE own interest. In 1053 they defeated and captured Pope Leo IX, and in 1059 Pope Nicholas II recognized Robert Guiscard (the Wary) as Duke of Apulia, Calabria, and Sicily — land which he agreed to hold as a fief from the Papacy. He proved a troublesome vassal, and conquered a number of papal possessions, and had to be excommunicated more than once; but the popes needed his aid to put down the robber barons in the vicinity of Rome, and later to resist the Holy Roman Emperor. Southern Italy was not entirely in Norman hands until the fall of Bari, the last Byzantine stronghold, in 107 1 ; and twenty more years passed before the conquest of Sicily was completed, although the Saracen capital, Palermo, was taken in 1072. Western Christianity not only gained at the expense of Islam by these Norman conquests, but those regions of southern Italy which the iconoclastic Emperor Leo had transferred to the Patriarch of Constantinople were now brought back under papal control. In 11 30 the Norman rulers were granted the title, King of Sicily. They built up a strong form of government, but their dynasty ended with the twelfth century, when the Holy Roman Emperor, Henry VI, who had married the Nor- man heiress, made good his claim to the Sicilian crown. In the Spanish peninsula, after the dismemberment of the Caliphate of Cordova in the early eleventh century, the Christian ex- Christian states gradually pushed their bound- thrspanish ar ies south at the expense of the Moslems, al- pemnsula though this was not accomplished without oc- casional setbacks and vicissitudes. The Christians often stopped to fight among themselves. Leon and Castile were at times united under one ruler into a strong military king- dom, and then again divided among several heirs. The progress of the Christian arms was also twice checked by fanatical hosts of Mohammedan barbarians from Africa who extended their sway into Spain and were called " Almo- ravides" and "Almohades" respectively. For example, in 1085, Alfonso VI of Castile and Leon, following up the successful campaigns of his father, took Toledo; but the next year he was decisively defeated by the Almoravides at 4