While Robert Guiscard was thus consolidating his power in the peninsula, an even harder task was being accomplished by his younger brother Roger, sometimes in alliance, and sometimes in fierce hostility with the Duke of Apulia. The grant of Nicholas II. had contemplated the extension of the Norman rule to Sicily. The divisions of the Mohammedan world had cut off the island from the Caliphate of the Fatimites, and its independent Ameers were hardly equal to the task of ruling the island and keeping in order a timid but refractory population of Christian serfs. [Sidenote: Roger’s conquest of Sicily, 1060–1101.] The increasing power of Robert was fatal to the independence of Roger in Calabria, and he gladly accepted the invitation of the discontented Christians of Messina to deliver them from the bondage of the infidel. In 1060 Roger led his first expedition to Sicily, which was unsuccessful. But early next year he came again, and this time the dissensions of the Mohammedans in Sicily enabled him to have friends among Saracens as well as Christians. In the summer of 1061 Robert came to his help. Messina was easily captured, and proved invaluable as the starting-point of later expeditions. The infidels were badly beaten at the battle of Castrogiovanni, and before the end of the year the standards of Roger had waved as far west as Girgenti. The first successes were not quite followed up. In 1064 the Normans were forced to raise the siege of Palermo. The compact Mussulman population of Western Sicily opposed a very different sort of resistance to the invaders from that which they had experienced in the Christian East. But the process of conquest was resumed after the capture of Bari had given Robert leisure to come to his brother’s help. In 1072 Palermo was taken by the two brothers jointly. Robert claimed the lion’s share of the spoil. Roger, forced to yield him the suzerainty of the whole island, and a great domain under his direct rule, including Palermo and Messina, threw himself with untiring zeal into the conquest of the parts of the island that still adhered to Islam. Thirty years after his first expedition, the last Saracens were expelled from the rocky fastnesses of the western coasts, and the inaccessible uplands of the interior. [Sidenote: The feudalisation of Naples and Sicily.] The Normans took with them to Italy their language, their manners, their art, and above all, their polity. On the ruins of the Greek, Lombard and Saracen power, the Normans feudalised southern Italy so thoroughly that the feudalism of Naples and Sicily long outlasted the more indigenous feudalism of Tuscany or Romagna. Freed from his grasping brother’s tutelage after 1085, Roger ruled over Sicily as count till his death in 1101. We shall see how his son united Sicily with Apulia in a single sovereignty, which has in various shapes endured as the kingdom of Naples or Sicily, until the establishment of a united Italy in our own days.