Sweyn (swān) [key], c.960–1014, king of Denmark (986–1014), son of Harold Bluetooth. Although baptized, he reverted to paganism and rebelled against his father, who was killed in battle. Sweyn was expelled shortly after his accession by the Swedish king Eric the Victorious, but his subsequent marriage to Eric's widow led to his restoration to the Danish throne and to an alliance with Sweden. At the battle of Svolder (1000) the Swedes and Danes defeated and killed King Olaf I of Norway and divided his kingdom. Sweyn had previously invaded England and exacted Danegeld from King Æthelred. He invaded England again in 1003–4 and in 1013, when the English finally submitted and accepted him as king. He died before his coronation. His son Canute succeeded him in England (1016) and Denmark (1018). The name also appears as Svein.