(born circa 1015, Normandy—died July 17, 1085, near Cephalonia, Greece, Byzantine Empire) Norman adventurer and duke of Apulia (1059–85). Born into a family of Norman knights, he joined his brothers and half brothers in southern Italy, defeating the Byzantines, Lombards, and papacy (1053) and taking over Apulia. He allied with the papacy (1059), agreeing to oppose the Byzantines and expel the Arabs from Sicily. His brother Roger (later Roger I) helped him to conquer Sicily and Calabria, and he gained control of Salerno in 1076, making it the capital of his duchy. Robert made an abortive attempt to gain the Byzantine throne (1083) but returned to Italy to defend Pope Gregory VII from his enemies.

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See also

• Communes of the Oise department