Nicholas Arnesson

Nicholas Arnesson (Old Norse Nikolás Árnason), died 1225, was a Norwegian bishop and nobleman during the Norwegian civil war era. He was a leader in the opposition against king Sverre of Norway and founder of the Bagler party. He is a chief antagonist in Sverris saga where he is portrayed as cowardly and deceitful.

Nicholas was the son of Ingrid Ragnvaldsdotter, the dowager queen of Norway, and her fourth husband Árni Ívarsson of Stoðreim. He was a half-brother of king Inge Haraldsson. Nicholas supported king Magnus Erlingsson in the civil war against king Sverre and took part in the battle of Ilevollen in 1180. This war ended with Magnus' death in 1184 and Sverre as sole king of Norway.

Nicholas was Bishop of Oslo from 1190 until his death. According to Sverris saga he was first made [Ancient Diocese of Stavanger|Bishop of Stavanger]] and then transferred to Oslo, but this is not supported by contemporary documents and is probably an attempt to discredit Nicholas. At this time relations between church and king were becoming increasingly bad with the archbishop forced into exile. In 1194 an upprising by former supporter of king Magnus ended in failure. Sverre charged Nicholas with treason, claiming he had been implicated. Nicholas was forced to take part in the crowning of Sverre the same year.

In 1195 Nicholas escaped to exile in Denmark. The next year he and other opponents of Sverre founded the Bagler party. As king they chose Inge Magnusson who was claimed to be the illegitimate son of Magnus Erlingson. The Baglers established themselves in the Viken area, which was both Nicholas' bishopric and king Magnus' old power base. Although they were at times driven out, Viken remained loyal to the Bagler cause to the end of the civil war.