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 Bavaria William II, Duke of Bavaria Duke William II of Bavaria-Straubing KG (5 April 1365—31 May 1417) was also count William IV of Holland, count William VI of Hainaut and count William V of Zeeland. He ruled from 1404 until 1417, when he died from an infection caused by a dog bite. William was a son of Albert I and Margaret of Brieg. William, allied with the Hooks, was in conflict with his father until 1394. In 1404 he succeeded him as Count of Holland, Zeeland and Hainaut and duke of Bavaria-Straubing. In 1408 in the Battle of Othée William and