A solo project by DARKTHRONE, STORM, DØDHEIMSGARD, EIBON and VALHALL drummer Fenriz (a.k.a. Gylve Nagell). The heavily Tolkein influenced ISENGARD, the project logo being a depiction of Thuringwethil from 'The Silmarillion', bowed in with a 1989 demo 'Sectres Over Gorgoroth' and the follow up 1991 session 'Horizons'. ISENGARD's debut album 'Vinterskugge' ('Winter Shadow') was issued in 1994 on the Peaceville Records subsidiary Deaf Records. A second album by Fenriz was released in late 1994 under the name of NEPTUNE TOWERS.

Dutch Black Metal act ZWARTKETTERIJ's 2005 album 'Sodomizer Dirty Sodomizer', released through GoatowaRex, included a cover version of ISENGARD's 'Neslepaks'.