Alan IV, Duke of Brittany of William the Bastard, Duke of Normandy (later to become known as William the Conqueror) support of rebels in Brittany against Alan's maternal uncle, Conan II. Conan II died in late 1066 during a campaign in Anjou, and was succeeded by Alan's parents, Conan's sister Hawise and her husband Hoel II. Hoel ruled as regent from Hawise's death in 1072 until Alan reached his majority in 1084. To prevent further hostilities during his invasion of England, William I married his daughter Constance to the new duke Alan in 1087. The marriage ceremonies may have taken place in Bayeux in Normandy.
William II, Duke of Aquitaine Magyars. William died soon after. In 924 the duke Raoul of Burgundy came up to the Loire river and William was forced to make his submission to him. Upon which Raoul, relieved that such a powerful vassal accepted his suzerainty, gave him back the counties of Berry and Macon and the town of Bourges. William II, Duke of Aquitaine William II the Young (died 12 December 926) was the Count of Auvergne and Duke of Aquitaine from 918 to his death, succeeding his uncle William I. William was son of the Acfred I of Carcassonne and Adelinde, William I's sister