Battle of Stamford Bridge

When Edward the Confessor died childless on 5 January 1066, the English magnates chose Harold Godwinson, Earl of Wessex, as king. Two foreign rulers claimed the throne: Duke William of Normandy and Harald Sigurdsson of Norway, who based his claim on an agreement said to have been made between his predecessor Magnus the Good and King Harthacnut. In September Harald sailed up the Ouse with a large fleet — 300 ships, according to one manuscript of the Anglo-Saxon Chronicle — joined forces with Harold's exiled brother Tostig, defeated the northern earls Edwin and Morcar at Fulford on 20 September and received the submission of York.

Harold, who had spent the summer guarding the south coast against William, marched north at great speed with his housecarls, passed through York and on 25 September fell on the Norwegians at the crossing of the Derwent, where they were waiting for hostages; many had left their mail coats with the ships. In the saga written by Snorri Sturluson in the 13th century, Harold rides up before the battle and offers his brother a share of the kingdom, but Harald only "seven feet of English ground, or as much more as he may be taller than other men". Harald was killed early on by an arrow in the throat; Tostig took command and fell in turn; the fighting went on for hours, and a counterattack by men hurrying from the ships under Eystein Orre was overwhelmed. Harold let the survivors, among them Harald's son Olaf, sail home after they swore never to attack England again; according to the Chronicle, 24 ships were enough to carry them.

Harald had served Yaroslav the Wise in Rus' and commanded Varangians in Byzantium before he became king of Norway in 1046. His death has traditionally been treated as the end of the Viking Age, although Scandinavian kings still sent expeditions to Britain and Ireland — Sweyn Estrithson of Denmark in 1069–1070 and Magnus Barefoot of Norway in 1098 and 1102–1103. The victory cost Harold dearly: on 28 September William landed at Pevensey, and the English army, weakened by the battle, had to march the length of the country to meet him.