William was born around 1028, in Falaise, Normandy. His father was Robert I, Duke of Normandy. When his father died in 1035, when William was only 7 years old, he was recognized as heir, with his great uncle serving as regent. Seven years later, he began to take more personal control. From 1046-1055, William dealt with a series of baronial rebellions. He married Matilda, daughter of Count Baldwin of Flanders in 1053. They had nine children together. They were William II of England, Henry I of England, Robert III, Duke of Normandy, Adela of Normandy, Adeliza, Richard, Duke of Bernay, Constance of Normandy, Cecilia of Normandy, and Agatha of Normandy.