The Chronicle of The Kings of Norway
Part 1 - Harald's Strife With Hake And His Father Gandalf
Harald  was but ten years old when he succeeded his father (Halfdan the Black). He became a stout, strong, and comely man, and withal prudent and manly. His mother's brother, Guthorm, was leader of the hird, at the head of the government, and commander (`hertogi') of the army. After Halfdan the Black's death, many chiefs coveted the dominions he had left.
Among these King Gandalf was the first; then Hogne and Frode, sons of Eystein, king of Hedemark; and also Hogne Karuson came from Ringerike. Hake, the son of Gandalf, began with an expedition of 300 men against Vestfold, marched by the main road through some valleys, and expected to come suddenly upon King Harald; while his father Gandalf sat at home with his army, and prepared to cross over the fiord into Vestfold.
When Duke Guthorm heard of this he gathered an army, and marched up the country with King Harald against Hake. They met in a valley, in which they fought a great battle, and King Harald was victorious; and there fell King Hake and most of his people. The place has since been called Hakadale. Then King Harald and Duke Guthorm turned back, but they found King Gandalf had come to Vestfold.
The two armies marched against each other, and met, and had a great battle; and it ended in King Gandalf flying, after leaving most of his men dead on the spot, and in that state he came back to his kingdom. Now when the sons of King Eystein in Hedemark heard the news, they expected the war would come upon them, and they sent a message to Hogne Karuson and to Herse Gudbrand, and appointed a meeting with them at Ringsaker in Hedemark.
Footnotes and references:
The first twenty chapters of this saga refer to Harald's youth and his conquest of Norway. This portion of the saga is of great importance to the Icelanders, as the settlement of their Isle was a result of Harald's wars. The second part of the saga (chaps. 21-46) treats of the disputes between Harald's sons, of the jarls of Orkney, and of the jarls of More. With this saga we enter the domain of history. — Ed.