In 995 CE Olaf Tryggvasson ascended the throne of Norway and quickly set about unifying the country, whose districts had enjoyed considerable autonomy before, by force.
It was partly a religious campaign, as Olaf was christian while some of the jarls were not.
Worshippers of Odin were forced to convert and if they refused, tortured to death.
By doing so, Olaf made many enemies, most notably Sweyn Forkbeard, king of Denmark, and Eirik Haakonsson.
The former had made an alliance with another Olaf, king of Sweden, against him.
Olaf Tryggvasson was angered by this and sought to fight his enemies.
He set sail to Wendland to gain allies, though met with little success.
On his return journey to Norway he sailed ahead with 11 ships, expecting the rest of his fleet to join him soon after his departure.
Among the 11 were some large drakkars: the Crane, the Serpent and the grandest of them all, the Long Serpent.
Sweyn convinced jarl Sigvald, leader of the Jomsvikings, who were allies of Olaf but were not christians, to betray Olaf and deliberately fail to support him.
At the place of the battle, perhaps near the island of Rügen or somewhere in the Øresund,
the alliance of Sweyn, Eirik and Olaf lay in ambush, totaling anywhere between 70 and 140 ships.
When Tryggvasson realized he had sailed into a trap, he lashed his ships together to provide a stable fighting platform and limit his opponent's advantage of numbers.
Both sides rained arrows, javelins and throwing axes on the other.
Jarl Eirik used his own ship, which had a prow reinforced with iron, to pry one ship after another loose from the defending formation and defeat them.
The Long Serpent was the last to be assaulted, but it held out long.
According to the legends Olaf Tryggvasson committed suicide by jumping overboard and drowning.
With Olaf out of the way, the victors divided Norway among themselves.
But Svolder did not settle the Norwegian issue.
Other battles followed: Nesjar in 1016 CE and Stiklestad in 1030 CE.
Finally Magnus the Good gained the thrown in 1035 CE, who unified Norway and made it christian.
War Matrix - Battle of Svolder
Viking Age 800 CE - 1066 CE, Battles and sieges