Sweyn Forkbeard all England in 1016, following the deaths of Æthelred and his son Edmund Ironside; he succeeded his brother as King of Denmark in 1019 and eventually also ruled Norway, parts of Sweden, Pomerania, and Schleswig. Cnut and his sons, Harold Harefoot and Harthacnut, ruled England over a combined 26-year period (1016–1042). After Harthacnut's death, the English throne reverted to the House of Wessex under Æthelred's younger son Edward the Confessor (reigned 1042–1066). Sweyn's daughter, Estrid Svendsdatter, was the mother of King Sweyn II of Denmark. Her descendants continue to reign in Denmark to this day. One of them, Margaret of
Edgar Ætheling Edgar. However, within months Robert left England, unhappy with William's failure to fulfil the pact between them, and Edgar went with him to Normandy. Having returned to England, Edgar went to Scotland again in 1093, on a diplomatic mission for William to negotiate with Malcolm, who was dissatisfied with the Norman failure to implement in full the terms of the 1091 treaty. This dispute led to war, and within the year Malcolm had invaded England and had been killed along with his designated heir Edward, eldest of his sons by Margaret, in the Battle of Alnwick. Malcolm's successor, his brother