n.
Italian Guglielmo known as William the Good
born 1154
died Nov. 18, 1189, Palermo, Kingdom of Sicily
Last Norman king of Sicily (116689).
His mother served as regent until 1171, after which he ruled alone, winning a reputation for clemency and justice. His friendship with Manuel I Comnenus ended when the Byzantine emperor thwarted William's proposed marriage to his daughter. Turning against the Byzantines, William allied with Frederick I Barbarossa. He agreed to his aunt's marriage to Frederick's son Henry (later Henry VI ), giving Henry a claim to Sicily. He attacked the Byzantines (1185) with early success but was defeated within sight of Constantinople.