I assume you are referring to William, Duke of Normandy, also known as William the Conqueror. Here are ten facts about him:

1. William was born in Normandy, France, in 1028 or 1029.
2. He became Duke of Normandy at the age of 8 or 9 after his father's death.
3. William led the Norman invasion of England in 1066, famously defeating King Harold Godwinson at the Battle of Hastings.
4. He was crowned King of England on Christmas Day in 1066.
5. William commissioned the Domesday Book, a survey of England's people and resources, in 1086.
6. He suppressed several rebellions in England during his reign, including the Revolt of the Earls in 1075.
7. William supported the Roman Catholic Church and sponsored the building of several churches and monasteries in England and Normandy.
8. He died in 1087 from injuries sustained during a battle against his son Robert.
9. William's reign marked the beginning of Norman rule in England, which lasted for over 200 years.
10. He is remembered as one of the most significant figures in English and European history, credited with transforming England into a centralized and feudal state.