Battle of the Helgeå
|Battle of the Helgeå|
|Commanders and leaders|
|Cnut the Great
Ulf the Earl
|~600 ships||~480 ships|
|Casualties and losses|
Battle of the Helgeå (Norwegian: Slaget ved Helgeå, Swedish: Slaget vid Helgeå) was a naval engagement which took place during 1026, between joint Danish and English forces and a combined Norwegian and Swedish force, at the estuary of a river called Helgeå in Sweden.
King Olaf II of Norway and King Anund Jakob of Sweden took advantage of the commitment of Danish King Cnut to England and began to launch attacks on the Danish in the Baltic Sea. The Swedish and Norwegian navies led by kings Anund Jacob and Olaf II lay in wait up a river for the navy of King Cnut, which was commanded by Danish earl Ulf Jarl. 
Cnut's navy was massive and his own ship is said to have been 80 metres long. The Swedish and the Norwegian kings ordered a large dam made of peat and lumber on the river. When the Danish navy sailed in, the water was released and a great many Danes and Englishmen drowned in the deluge. However, Cnut's men were apparently able to win the battle.
The apparent victory left Cnut as the dominant leader in Scandinavia. At some time after the battle, Cnut subjugated the core provinces of Sweden around Lake Mälaren where he had his own coins minted in Sigtuna.
The battle is retold in skaldic poetry and in sources such as the Danish Gesta Danorum by Saxo Grammaticus and the Icelandic Saga of Olaf the Holy by Snorri Sturluson. Opinions are divided on whether the location was at Helgeå in Uppland or the Helgeå of eastern Skåne.
- A.D. 1025. This year went King Knute to Denmark with a fleet to the holm by the holy river; where against him came Ulf and Eglaf, with a very large force both by land and sea, from Sweden. There were very many men lost on the side of King Knute, both of Danish and English; and the Swedes had possession of the field of battle.
- Rosborn, Sven Den skånska historien (Vikingarna. Malmö: 2004)
- The Battle of Helgå, as told in the Saga of Olaf Haraldsson, by Snorri Sturluson.