County of Sicily was created by Robert Guiscard in 1071 for his younger brother Roger Bosso. Guiscard himself had received the title Duke of Sicily ("dux Siciliae") in 1059 from Pope Nicholas II as encouragement to conquer it from the Muslims. In 1061 the first permanent Norman conquest (Messina) was made and in 1071, after the fall of Palermo, the capital of the emirate and future capital of the county, Guiscard invested Roger with the title of count and gave him full jurisdiction in the island save for half the city of Palermo, Messina, and the Val Demone, which he retained for himself.
Sicily was the first part of Italy to be taken by general Belisarius, who was commissioned by Eastern Emperor Justinian I as part of an ambitious attempt to restore the whole Roman Empire, thereby uniting the Eastern and the Western halves. Sicily was used as a base for the Byzantines to conquer the rest of Italy, with Naples, Rome, Milan, and the Ostrogoth capital Ravenna falling within five years. However, new Ostrogoth king Totila drove down the Italian peninsula, plundering and conquering Sicily in 550. Totila, in turn, was defeated and killed in the Battle of Taginae by Byzantine general Narses