Ihsahn (born 1975 as Vegard Sverre Tveitan) is a Norwegian composer, guitar, bass, keyboard player and vocalist. He is best known for his work with Norwegian black metal band Emperor. He has appeared in Thou Shalt Suffer, up until March 4, 2006, played in Peccatum with his wife Ihriel (real name Heidi S. Tveitan), and now devotes himself to his solo project, Ihsahn. In his very early releases, he went by the name Ygg.

Born in the town of Notodden, Norway, Tveitan began playing piano at seven and guitar at ten and began recording songs shortly thereafter. His influences range from heavy metal, classical, ambient, and techno. He grew up on a large farm in rural Norway.

Tveitan first met his partner, Tomas Haugen (also known as Samoth) at the age of thirteen at a music seminar. Tveitan gained Haugen's attention with his Iron Maiden patches [4]. In 1991 they formed Thou Shalt Suffer together, a death/black metal band where Tveitan was guitarist and keyboardist. They produced several releases before Haugen left the band. Tveitan was left as the only member of the band and continues it to this day as a side-project.

After the departure of Haugen from Thou Shalt suffer, the two formed Emperor where Tveitan again played guitar. Emperor had a much more refined black metal sound which showcased Tveitan's developing keyboard sound, a distinct feature that would appear in his later releases. The band at this time received much support and encouragement from black metal pioneer Euronymous and after several demos, In the Nightside Eclipse was released to much acclaim.

Shortly thereafter, bandmates Haugen and Bård Eithun (also known as Faust) were arrested and imprisoned leaving Tveitan to his own devices. He retreated to a property owned by his family to compose much of what would later become Anthems to the Welkin at Dusk, which was recorded after the parole of Haugen.

In 1995 the cult album Blood Must Be Shed from Zyklon-B was released featuring members of Emperor and Satyricon, with Tveitan on synth. In 1998 Tveitan formed, along with his wife Heidi Tveitan (AKA Ihriel), the more experimental project Peccatum. In 1999 Emperor released IX Equilibrium.

Peccatum would feature his trademark synth sound as well as clean and black vocals. Over the years Peccatum has released five albums and EPs and was Tveitan's main project until the project was ended in early March 2006.

In 2001, the final Emperor album was released. A studio album, Prometheus: The Discipline of Fire & Demise was entirely composed by Tveitan and featured more complex orchestration than previous works. It had significantly less synth than before. It was at this time Emperor mutually decided to dissolve, leaving the band with more time to focus on side projects.

In December 2002, Ihsahn won the "Notodden Kommunes Kulturpris", a culture prize given by his home city, Notodden, which has around 12,500 inhabitants. He won the prize because he is considered the most well known inhabitant of Notodden and a great musician, who works as a music teacher, and arranges a lot of concerts for unknown bands.[citation needed] The fact that his band sold more than 500,000 copies was also a reason for getting the prize.

On September 30th 2005, Emperor made a surprise return at Scream magazine's 15-year anniversary party in Oslo at Rockefeller, a rock concert venue. The move was kept top secret, was only known by a handful of people, and they played three songs only. This was to announce the reuniting of the band for a few shows around Europe and America in 2006, namely at Wacken and Inferno Festival.

His first solo album The Adversary was released in April 2006. All work was done by him with the exception of percussion, which was done by Asgeir Mickelson. It showcases his progressive influences as well as heavy metal, black metal and classical music. The album was recorded at Symphonique Studios in Norway and is to be released on his label Mnemosyne Productions, which was formed in 2003 with Ihriel. A video accompanies the track "Invocation."

As well as being a talented musician, Tveitan is also a capable artist and once considered doing the artwork for a Thou Shalt Suffer album. He presently lives in Notodden, Norway with his wife and one dog, an Akita Inu. He also teaches music at the local school.