Harald Fairhair

Harald Fairhair (c. 850 – c. 932) was the first King of Norway. According to traditions today in Norway and Iceland, during the 12th and 13th centuries, he was king from 872 to 930. Most of what we know about him comes from several sagas, written up to three centuries after he died.
Life.
He was the son of Halvdan the Black. Harald was the first petty king to gain control of the coastal areas of Norway. After the battle of Hafrsfjord in 872 Harald became king of most of Norway. It was the last of a series of battles between Harald and other feudal states in Norway. 
Because of Skaldic poems (poems honouring heroes in Scandinavia), we know that he was successful in fighting against his opponents in Norway. Eric Bloodaxe and Haakon the Good, his two sons, became King after he died of old age. 
Fairhair may have had as many as 11-20 sons according to different Sagas. Twelve of them became Kings and were all assigned land.