William I (1028 - 1087), known as William the Conqueror, was the first Norman king of England, who ruled from 1066 until his death in 1087. He was the Duke of Normandy from 1035 onwards, so it's also known as the William of Normandy. Normans argued that William was the first king of England, although there were kings in England before him. William I was the first king of united England, who united the smaller Saxon kingdoms, who had their own rulers, before William I became king of them all.