Formed in 1989 as Stigma Diabolicum by Snorre Ruch and Marius Vold who recorded a demo in the winter of that same year. In 1990 Harald Eilertsen and Bård Eithun joined on bass and drums. In 1991 they changed their name to the simplistic english Thorns due to the escalation of latin names in the black metal scene. Harald and Snorre recorded "Grymyrk" - a bass and guitar set of 6 songs for Bård and Marius to listen to for rehearsals. A couple of additional rehearsals were recorded with this line-up on a cassette deck. In 1992 two tracks were recorded with session musicians in a school studio, known as the "Trøndertun" tape. Later in 1992 Euronymous and Snorre decided to play second guitar in each other's bands (Mayhem and Thorns), resulting in the break-up of Thorns.
After only a few month Snorre left Mayhem and reactivated Thorns - from here on a one-man project.