William the Conqueror (1028–1087), Duke of Normandy, changed history in 1066 by defeating King Harold II at the Battle of Hastings, becoming the first Norman King of England. His rule reshaped the kingdom through feudalism, castle-building, and the monumental Domesday Book, a survey of England’s wealth. Though often brutal, William’s reign forged a stronger monarchy and tied England to continental Europe. His legacy lives in both conquest and consolidation, marking the birth of medieval England