They started out as a pure death metal band but later incorporated more and more doom metal incluences. The band was started in 1990 by Nicklas "Terror" Rudolfsson under the name Desiderius which was quickly changed to Runemagic. First, the band consisted solely of Rudolfsson, but he was later joined by Robert “Reaper” Pehrsson. After a few demos the band fall apart in 1993. Rudolfsson restored Runemagic in 1997 with Fredrik Johnsson on guitar and Peter Palmdahl on bass; he also added the "k" to the name (see also magick). A rehearsal demo with Nicklas on drums was recorded and sent to Century Media Records, which got them a record deal for three albums.
Many band members later, in 2000 the band parted with Century Media and eventually landed on the Norwegian label Aftermath Music. The band has been releasing at least one album a year on that label since 2002. Most recently the band slowed down on their latest opus Envenom, which consists of merely five long songs.
Rudolfson and Karlsson are also participating in the funeral doom project The Funeral Orchestra.