On September 9, 999 or 1000, the Battle of Svolder was fought in the western Baltic Sea between King Olaf Tryggvason of Norway and an alliance of his enemies.
The background of this naval battle was the unification of Norway into a single state; long-standing Danish efforts to gain control of the country, and the spread of Christianity in Scandinavia.
King Olaf was sailing home after an expedition to Wendland (Pomerania), when he was ambushed by an alliance of Svein Forkbeard, King of Denmark, Olof Skötkonung (also known as Olaf Eiríksson), King of Sweden, and Eirik Hákonarson, Jarl of Lade.
Olaf had only 11 warships in the battle against a fleet of at least 70.
His ships were captured one by one, last of all the Ormen Lange, which Jarl Eirik captured as Olaf threw himself into the sea. After the battle, Norway was ruled by the Jarls of Lade as a fief of Denmark and Sweden.
The exact location of the battle is disputed; according to Icelandic sources, the battle took place near a place called Svolder, while others propose Øresund as the place of this battle.
The kings’ sagas, which were written approximately two centuries after , the event took place, are the most detailed sources on the battle.
They describe the battle and the events leading up to it in vivid detail, but historically they are not particularly trustworthy.
The sagas ascribe the causes of the battle to Olaf Tryggvason’s ill-fated marriage proposal to Sigrid the Haughty and his problematic marriage to Thyri, sister of Svein Forkbeard.
As the battle starts Olaf is shown dismissing the Danish and Swedish fleets with ethnic insults and bravado while admitting that Eirik Hákonarson and his men are dangerous because “they are Norwegians like us”. The best known episode in the battle is the breaking of Einarr Þambarskelfir’s bow, which heralds Olaf’s defeat.
The battle has inspired a number of ballads and other works of literature.