Sven Estridsson
The Battle of Niså ("Slaget ved Niså") was a naval battle fought on 9 August 1062 between the forces of Norwegian king Harald Hardrada and king Sweyn II of Denmark. Harald had claimed the Danish throne since 1047, and had launched raids into Denmark ever since. With his invasion in 1062, he wanted to decisively defeat the Danes, and thus finally be able to conquer Denmark. The battle was won clearly by the Norwegians, but since many Danes managed to escape, including Sweyn, it proved indecisive in Harald's attempt to conquer Denmark.