William the Conqueror, originally known as William I of England, was a powerful duke from Normandy in France. He became famous for leading the Norman Conquest of England in 1066, which began after he claimed the English throne. His victory at the Battle of Hastings marked a significant turning point in English history. After his conquest, William implemented changes in governance and land ownership, redistributing land to his loyal followers. He commissioned the Domesday Book, a comprehensive survey of his new kingdom, which helped establish a system of taxation and administration. William's reign laid the foundation for the future of England.