[1] Olav Gudbrandsson was the son of Gudbrand Skavhoggsson (Guðbrandr Skafhǫggsson) and Maria Øysteinsdotter (María Eysteinsdóttir), the daughter of King Eystein I of Norway and his wife Ingebjørg Guttormsdatter.
Olav was fostered by Sigurd Agnhatt (Sigurðr agnhǫttr) in the Oppland region of eastern Norway.
After Erling returned to Norway to fight this uprising, Olav and his men attacked Erling in an ambush at Rydjokul in Sørum (Overfallet på Rydjøkul) on 2 February 1167.
Sigurd Agnhatt was killed in the battle, but Olav Ugjæva escaped and went to Denmark.
[3] The story of Ugjæva is mentioned in the Kings' sagas Heimskringla and Fagrskinna.