Agnar the Unwavering was a Nord who was the chieftain of the village of Thirsk in Solstheim. His wife was Svenja Snow-Song, also a Nord who survived the Thirsk Mead Hall Massacre where the Udyrfrykte went on a destructive rampage and killed all of the patrons of the Thirsk Mead Hall except for her. Agnar became the chieftain of Thirsk after the Slayer of the Udyrfrykte.
During the Oblivion Crisis, Agnar, through the questioning of researchers and adventurers, discovered that the Uderfrykte was not the only one of its kind, but was only the offspring of a far greater beast known as the Uderfrykte Matron. As his wife Svenja was still haunted by dreams of the Udyrfrykte's attack on the Thirsk Mead Hall, Agnar became determined to search for and kill the Matron.
Joined by his wife, Agnar set off to Skyrim to search for the beast. Finding the beast was far from easy, and Agnar searched for months without finding any trace of the Uderfrykte Matron. Eventually, however, a local shepherd in the highlands of Skyrim gave Agnar the news he had been waiting for. The Uderfrykte Matron had been sighted in Cyrodiil.
Agnar and his wife followed the creature into Cyrodiil and tracked the beast through the Jerall Mountains, north of Bruma. The two Nords set up camp at Dive Rock, the highest natural observation point in all of Cyrodiil, where they waited to catch a sign of the Uderfrykte Matron.
Eventually, they found the beast and Agnar and Svenja attacked the Uderfrykte Matron. Unfortunately, this did not go well at all, their weapons proved ineffective and Svenja was swallowed whole. Agnar fled, but was set upon by the Uderfrykte Matron at his camp at Dive Rock while he was writing in his journal. Agnar was slain; however, his journal entry gave a later adventurer the necessary information to finally find and slay the beast.