The traditional dynasty of the unifiers of Norway, from Harald Fairhair through Saint Olaf and Harald Hardrada.
Norwegian tradition holds that Harald Fairhair united the many petty kingdoms of Norway into one realm after a decisive sea-battle at Hafrsfjord, traditionally dated around 872. This account survives mainly through Icelandic sagas written three centuries later, so the details — and the completeness of his unification — are uncertain, but Harald became the ancestor-figure of the Norwegian monarchy.
His many sons fought over the inheritance. Eric Bloodaxe, remembered for killing his brothers, was driven out and later ruled as a Viking king at York, while the English-raised Haakon the Good returned to take Norway and make the first royal attempts at Christianisation.
Two kings named Olaf drove Norway’s conversion, both through force. Olaf Tryggvason, a former Viking, imposed Christianity harshly during his short reign before dying at the sea-battle of Svolder around 1000. A generation later Olaf Haraldsson — Saint Olaf — completed the work, and though he was killed by rebellious chieftains at Stiklestad in 1030, his cult as Norway’s patron saint quickly made him more powerful in death than in life.
The sagas surround both kings with legend, and their stories must be read as tradition shaped by later Christian memory as much as as documentary history.
Saint Olaf’s half-brother Harald Sigurdsson, called Hardrada ("hard-ruler"), fled after Stiklestad to serve in the Varangian Guard at Constantinople before returning to claim Norway in 1046. A formidable and ruthless king, he founded Oslo and warred for years against Denmark.
In 1066 he invaded England to claim its throne, but was defeated and killed by Harold Godwinson at the Battle of Stamford Bridge — a defeat traditionally taken to mark the end of the Viking age, days before the Norman landing at Hastings.
Harald Hardrada’s line continued through his son Olaf III "the Peaceful", whose long reign brought stability and the growth of Norwegian towns, and his grandson Magnus Barefoot, who campaigned aggressively around the Irish Sea and the Scottish isles before dying in Ireland in 1103.
Magnus’s son Øystein I and his brothers ruled jointly, developing Norway’s church, law, and trade, in a more settled age than that of their raiding ancestors.
The Fairhair dynasty gave Norway its founding myth, its conversion, and its patron saint. The cult of Saint Olaf and the idea of a single Norwegian kingdom descended from Harald Fairhair shaped Norwegian identity for the rest of the Middle Ages.
When the direct line faltered in the twelfth century, Norway fell into decades of civil war from which a new dynasty, the House of Sverre, eventually emerged.