The Chronicle of The Kings of Norway
Part 3 - Halfdan's Marriage
Halfdan the Black got a wife called Ragnhild, a daughter of Harald Gulskeg (Goldbeard), who was a king in Sogn. They had a son, to whom Harald gave his own name; and the boy was brought up in Sogn, by his mother's father, King Harald.
Now when this Harald had lived out his days nearly, and was become weak, having no son, he gave his dominions to his daughter's son Harald, and gave him his title of king; and he died soon after. The same winter his daughter Ragnhild died; and the following spring the young Harald fell sick and died at ten years of age.
As soon as Halfdan the Black heard of his son's death, he took the road northwards to Sogn with a great force, and was well received.
He claimed the heritage and dominion after his son; and no opposition being made, he took the whole kingdom. Earl Atle Mjove (the Slender), who was a friend of King Halfdan, came to him from Gaular; and the king set him over the Sogn district, to judge in the country according to the country's laws, and collect scat upon the king's account. Thereafter King Halfdan proceeded to his kingdom in the Uplands.