Knud the Great was the youngest son of the Danish king, Sweyn Forkbeard, who died during an invasion of England in 1014. Sweyn’s oldest son Harald became king of Denmark and Knud returned to England with an invasion fleet in the summer of 1015, where he found a divided nation, locked in factions and succession disputes. When the king of Wessex, Æthelred, died in April 1016 and was succeeded by his son Edmund, many disaffected nobles swore fealty to Knud, who defeated Edmund at the Battle of Ashingdon (18 October 1016) in Essex. A deal was struck whereby Edmund retained Wessex while Knud ruled all of England north of the Thames, but Edmund’s death in November 1016 left Knud king of all England. Three years later his brother Harald also died and he was able to claim the crown of Denmark. Within two years of becoming Danish king he started to lay claim to Norway, and by the late 1020s he was asserting that he was “King of all England, and of Denmark, and of the Norwegians and part of the Swedes.” In addition, he received tribute from the vassal states of the Wends on the Baltic coast, Scotland, Wales, and parts of Ireland. As ruler of a North Sea Empire, which encompassed the Viking homelands as well as England, he was able to protect England from sea-borne raids, leading to two decades of peace, in which the Christian kingdom of England stabilized and the Church was fully recognized and supported, trade and Anglo-Scandinavian art flourished, and the rule of law was respected. On Knud’s death in 1035 his sons and successors proved incapable of retaining control of the North Sea Empire and by 1042 it had broken up.
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