Ivar Skontorp Peersen, best known by his stage name Ivar Bjørnson, is a Norwegian musician. He is a founding member and the main songwriter of the extreme metal band Enslaved, and has previously been a member of the metal band Borknagar and collaborated with Einar Selvik on several albums. He has released sixteen studio albums with Enslaved and won five Norwegian Spellemann Awards with the band.