England in the high Middle Ages
- The Norman conquest of England was the 11th-century invasion and occupation of England by an army of Norman, Breton, and French soldiers led by Duke William II of Normandy, later William the Conqueror.
- William's claim to the English throne derived from his familial relationship with King Edward who died and was succeeded by his brother brother-in-law Harold Godwinson.
- The Norwegian king Harald Hardrada invaded northern England in September 1066, was victorious at the Battle of Fulford, but Harold defeated and killed him at the Battle of Stamford Bridge on 25 September 1066.
- William's force defeated Harold, who was killed in the engagement
- To control his new kingdom, William gave lands to his followers and built castles commanding military strong points throughout the land. Other effects of the conquest included the court and government, the introduction of Norman French as the language of the elites, and changes in the composition of the upper classes, as William enfeoffed lands to be held directly from the king.