Ihsahn (born October 10, 1975 as Vegard Sverre Tveitan) is a Norwegian composer, multi-instrumentalist, and vocalist. He is best known for his work with Norwegian black metal band Emperor. He has appeared in Thou Shalt Suffer, played in Peccatum with his wife Ihriel (real name Heidi S. Tveitan), and now devotes himself to his solo albums.

His instructional videos on music have appeared in online publications such as Guitar World. In style terms, his solo work and work with other artists have shown multiple musical forms from classical music to industrial metal to progressive metal and more. In terms of his personal beliefs, he has expressed support for Satanism and social darwinist thought while also showing respect to concepts such as meditation, stewardship of the environment, and traditional paganism as well as condemning acts of criminality and religious intolerance such as church arson.