Snorri Sturluson writes in Harald Fairhair's saga that Harald Fairhair disputed the Swedish king Eric Eymundsson's hegemony in what is today southern Norway.
He attacked and forced Viken to accept his rule and then plundered and burnt in Rånrike.
In the spring, they put stakes in Göta älv to stop Harald's ships.
Harald Fairhair put his ships alongside the stakes and plundered and burnt everything he could reach.
Harald then proclaimed himself the ruler of all land north of Göta älv and north and west of lake Vänern and placed Guttorm Haraldsson to defend the region with a large force.