William the Conqueror eldest son. William was the son of the unmarried Robert I, Duke of Normandy, by Robert's mistress Herleva. His illegitimate status and his youth caused some difficulties for him after he succeeded his father, as did the anarchy that plagued the first years of his rule. During his childhood and adolescence, members of the Norman aristocracy battled each other, both for control of the child duke and for their own ends. In 1047 William was able to quash a rebellion and begin to establish his authority over the duchy, a process that was not complete until about 1060. His marriage
William I, Duke of Bavaria William I, Duke of Bavaria William I, Duke of Bavaria-Straubing (Frankfurt am Main, 12 May 1330 – 15 April 1389, Le Quesnoy), was the second son of the emperor Louis IV the Bavarian from his second wife Margaret of Holland and Hainaut. He was also known as William V, Count of Holland, as William III, Count of Hainaut and as William IV, Count of Zeeland. In 1345 William's father was conferring Hainaut, Holland, Zeeland and Friesland upon his wife Margaret, and shortly later also upon their son William. After his father's death in 1347 William ruled Bavaria, Holland and Hainaut