County of Sicily with Robert Guiscard. In fact, the seat of Roger I's government was the Calabrian town of Mileto. According to the historians Agostino Inveges and Matteo Camera Roger I started to use the title ""Great Count of Sicily and Calabria"" since 1096. After the death of Roger I the major change was the transfer of the capital: Palermo became the capital in 1112, when Roger II was invested with the County, after the regency of the mother Adelaide del Vasto. With this change, Sicily come to be governed by the central government, while the Calabrian territories became a provincial administrative unit.
Roger II of Sicily the fleet by two Greeks, first Christodulus and then George of Antioch, whom he made in 1132 "ammiratus ammiratorum" or "Emir of Emirs", in effect prime vizier. (This title later became the English word admiral). Roger made Sicily the leading maritime power in the Mediterranean. Roger II had a kingdom where a Muslim scholar such as al-Idrisi could draw from a variety of intellectual traditions, because Sicily is positioned in the center of the Mediterranean and was a major stopping point for people traveling across the Mediterranean. Sicily had been run by several different groups in its history and Sicily