William Duke of Normandy (c. 1028-1087), usually known as William the Conqueror was the first Norman King of England, reigning from 1066 until his death in 1087.
In the 1050’s and early 1060’s, William became a contender for the throne of England held by the Childless Edward the Confessor, his first cousin removed.
There were other claimants. Including the powerful English earl Harold Godwinson, whom Edward had named as King on his deathbed, in January 1066.
William argued that Edward had previously promised the throne to him, and that Harold had sworn to support his claim.
Throughout the summer of 1066, William assembled an army and an invasion fleet in Normandy. This force included, in addition to troops from William’s own territories of Normandy and Maine, large numbers of mercenaries, allies and volunteers from Brittany, Northeast France and Flanders.