William I, also known as William the Conqueror, William, the Bastard or William of Normandy, French terms Guillaume le Conquérant or Guillaume le Bâtard or Guillaume de Normandie, (born c. 1028, Falaise, Normandy now France, died September 9, 1087, Normandy), duke of Normandy (as William II) from 1035 and King of England as William I from 1066, will go on record as the most outstanding King and ruler of the Middle Ages and beyond. He made himself the mightiest nobleman in France and then changed the course of England’s history by conquering the country.