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, Duke of Brunswick the accession of Ernest Augustus, Duke of Brunswick, the son of the Crown Prince of Hanover, in 1913. William died unmarried, but had a number of illegitimate children. William, Duke of Brunswick William, Duke of Brunswick (; 25 April 1806 – 18 October 1884), was ruling duke of the Duchy of Brunswick from 1830 until his death. William was the second son of Frederick William, Duke of Brunswick-Lüneburg, and after the death of his father in 1815, was under the guardianship of King George IV of the United Kingdom. He became a Prussian major in 1823. When his brother, Charles,