Haakon I (ca. 920 – 961) (Old Norse: (Old Norse: Hákon Aðalsteinsfóstri, Norwegian: Håkon Adalsteinsfostre), surnamed the Good, was the third king of Norway and the youngest son of Harald Fairhair.

Haakon was fostered by King Athelstan of England, as part of a peace agreement made by his father. The English king brought him up in the Christian religion, and on the news of his father’s death provided him with ships and men for an expedition against his half-brother Eirik Bloodaxe, who had been proclaimed king. On his arrival in Norway, Haakon gained the support of the landowners by promising to give up the rights of taxation claimed by his father over inherited real property.

Eirik fled and thereafter concentrated his efforts in the British Isles, eventually meeting a violent end there. His sons allied themselves with the Danes, but were invariably defeated by Haakon, who was successful in everything he undertook except in his attempt to introduce Christianity, which aroused an opposition he did not feel strong enough to face. He was killed at the Battle of Fitje in 961, after a final victory over Erik’s sons. So entirely did even his immediate circle ignore his religion that a court skald composed a poem on his death representing his welcome by the heathen gods into Valhalla.

The succession issue was settled as Harald II, third son of Eric, ascended the throne. However the Norwegians were severely tormented by years of war and welcomed the Danish invading force led by Harold Bluetooth.