There was a man, by name Svein, a son of Earl Ulf, and grandson of Thorgils Sprakaleg. Svein's mother was Astrid, a daughter of King Svein Forkbeard. She was a sister of Canute the Great by the father's side, and of the Swedish King Olaf Eirikson by the mother's side; for her mother was Queen Sigrid the Haughty, a daughter of Skoglar Toste.
Svein Ulfson had been a long time living with his relation the Swedish king, ever since King Canute had ordered his father Ulf to be killed, as is related in the saga of old King Canute, that he had his brother-in-law, Earl Ulf, murdered in Roskilde; and on which account Svein had not since been in Denmark. Svein Ulfson was one of the handsomest men that could be seen; he was very stout and strong, and very expert in all exercises, and a well-spoken man withal. Every one who knew him said he had every quality which became a good chief.
Svein Ulfson waited upon King Magnus while he lay in the Gaut river, as before mentioned, and the king received him kindly, as he was by many advised to do; for Svein was a particularly popular man. He could also speak for himself to the king well and cleverly; so that it came at lasf to Svein's entering into King Magnus's service, and becoming his man. They often talked together afterwards in private concerning many affairs.