ROGER I. (1031-1100, ruler of Sicily, was the youngest son of Tancred of Hauteville. Arriving in Southern Italy soon after 1057, he shared with Robert Guiscard the conquest of Calabria, and in a treaty of 1062 the brothers apparently made a kind of "condominium" by which each was to have half of every castle and town in Calabria. Robert now commissioned Roger to reduce Sicily, which contained, besides the Muslims, numerous Greek Christians subject to Arab princes who had become all but independent of the sultan of Tunis. In May 1061 the brothers crossed from Reggio and captured Messina. After Palermo had been taken in January 1072 Robert Guiscard, as suzerain, invested Roger as count of Sicily, but retained Palermo, half of Messina and the north-east portion of the island. Not till 1085, how ever, was Roger able to undertake a systematic crusade. In March 1086 Syracuse surrendered, and when in February 1091 Noto yielded the conquest was complete. Much of Robert's suc cess had been due to Roger's support. Similarly the latter sup ported Duke Roger, his nephew, against Bohemund and other rebels, in return for which the duke surrendered to his uncle in 1085 his share in the castles of Calabria, and in 1091 the half of Palermo.
At the enfeoffments of 1072 and 1092 no great undivided fiefs were created, and the mixed Norman, French and Italian vassals owed their benefices to the count. No feudal revolt of importance therefore troubled Roger. Politically supreme, the count became
master of the insular Church. While he gave full toleration to the Greek Churches, he created new Latin bishoprics at Syracuse and Girgenti and elsewhere, nominating the bishops personally, while he turned the archbishopric of Palermo into a Catholic see. The Papacy granted to him and his heirs in 1098 the Apostolic Legate ship in the island. Roger was tolerant towards Arabs and Greeks, allowing to each race the expansion of its own civilization. In the cities the Muslims, who had generally secured such terms of surrender, retained their mosques, their kadis, and freedom of trade ; in the country, however, they became serfs. He drew from the Muslims the mass of his infantry, but the Latin element began to prevail with the Lombards and other Italians who flocked into the island in the wake of the conquest, and the conquest of Sicily was decisive in the steady decline of Mohammedan power in the western Mediterranean. Roger, the "Great Count of Sicily," died on June 22, no 1, and was buried in S. Trinita of Mileto. His third wife, Adelaide, niece of Boniface, lord of Savona, gave him two sons, Simon and Roger, of whom the latter succeeded him.