Henry I of France whose death Henry was left to deal with his rebel sibling. In 1032, he placated his brother by giving him the duchy of Burgundy which his father had given him in 1016. In an early strategic move, Henry came to the rescue of his very young nephew-in-law, the newly appointed Duke William of Normandy (who would go on to become William the Conqueror), to suppress a revolt by William's vassals. In 1047, Henry secured the dukedom for William in their decisive victory over the vassals at the Battle of Val-ès-Dunes near Caen; however, Henry would later support the barons against
William V, Duke of Aquitaine William V, Duke of Aquitaine William the Great (; 969 – 31 January 1030) was duke of Aquitaine (as ) and count of Poitou (as or III) from 990 until his death. Upon the death of the emperor Henry II, he was offered the kingdom of Italy but eventually declined to contest the title against Conrad II. He was the son and successor of William IV by his wife Emma of Blois, daughter of Theobald I of Blois. He seems to have taken after his formidable mother, who ruled Aquitaine as regent until 1004. He was a friend to Bishop