Normans

   Byzantium's (q.v.) chief western foes in the 11th and 12th centuries. The Normans ("Northmen") were Vikings who emigrated to southern Italy (qq.v.) in the late 10th century; by 1071 the last Byzantine stronghold there, Bari (q.v.), had fallen into their hands. They essentially conquered Sicily from the Arabs (qq.v.) between 1060-1072, with the final conquest in 1091. Robert Guiscard and his son Bohemund (qq.v.) attacked Dyrrachion and other cities along the Via Egnatia (qq.v.) from 1081 until Robert's death in 1085. At the same time, Normans entered Byzantine service as mercenaries, some of them, e.g., Hervé Frankopoulos and Roussel de Bailleul (qq.v.), rising to high military commands. The Treaty of Devol (q.v.) in 1108 with Bohemund temporarily halted Norman aggression, but it revived later in the 12th century with Roger II's attack on Greece (qq.v.) in 1147-1148, and with the brief Norman occupation of Thessalonike (q.v.) in 1185.