William I of Cagliari

William I (c. 1160–1214), royal name Salusio IV, was the judike of Cagliari, meaning "King", from 1188 to his death. His descendants and those of his immediate competitors intermarried to form the backbone of the Italian Aristocracy, and ultimately their descendants in the Medici clan are precursors to, and definers of later royalty and claims thereto.