Espoo's SLUGATHOR was forged in the Autumn of 1999 by lead vocalist Nebiros, guitarist Tommi Grönqvist, bassist Tatte and drummer Immu (Ilmari Jalas). The quartet debuted with a brace of 2000 demos 'Delicacies Of The Cadaver' in March and 'Fabric Of The Multiverse'. Both of these sessions would be subsequently released by the German based Perverted Taste label as limited edition 7" singles. In early 2001 SLUGATHOR underwent a major line-up overhaul with founders Tommi Grönqvist and Ilmari Jalas being joined by new musicians Axu Laakso on vocals and guitarists Tuoppi (a.k.a. Tuomas Lintulaakso) of DE LIRIUM'S ORDER, and Antti Oinonen, the latter a member of DEEP RED and holding APOPLEXY, EXCREMENT and, as "Necroterror", CADAVERIC INCUBATOR credentials. Laakso's scene associations included DEEP RED, GOATHORDE, NIGHT MUST FALL and THORNGOAT.

SLUGATHOR's 2002 split single for Snuff Records, 'Creation .44', shared with DEEP RED, seeing Tommi on bass guitar, included a cover version of BOLT THROWER's 'Remembrance'. A concert recorded at the Semifinal, Helsinki in December 2002 would be released in Poland by the Time After Time label as a live cassette 'Crush Skulls And Bones'. The band signed to the Polish Agonia label for their inaugural album 'Unleashing The Slugathron' in late 2003. A cassette version was issued in Finland, restricted to 333 copies, by Northern Sound.

May 2004 dates in Finland saw WATAIN on a package billing alongside WATAIN, ANXIOUS DEATH and KAAMOS. That same year the group recorded further demos, from which the song 'Legions Of The Undead' was included on the compilation album 'Metal On Metal - Finnish Undergound Metal Collection'.

Tragedy hit the band on April 15th 2005 when Tuomas Lintulaakso was stabbed to death. In the wake of this event Oinonen briefly switched back to guitar from bass whilst Jarno Nurmi of NERLICH, NOWEN and NIGHT MUST FALL tried out on bass. Oinonen resumed his post on guitar and Juuso Heikkilä from NIGHT MUST FALL, GENERAL WINTER and TYRANNY filled the bass position. In this formation SLUGATHOR appeared at the festivals 'Murder Art' in Moscow, Russia and 'Jalometalli' in Oulu, Finland.

In 2006 drummer Ilmari Jalas, as 'Imperator', forged SATANIC TORMENT involving a quartet of scene veterans from the underground extreme Metal scene with singer H. Necrophiliac Ju Von Nen, of DEVIL LEE ROT, EVOKED CURSE, GOATSODOMY, SACRIFICIAL DAGGER, TRISTITIA, PAGAN RITES and WITCHTIGER, guitarist Kaosbringer, from NEUTRON HAMMER, SACRIFICIAL DAGGER and SYÖPÄ, and bassist Tooloud of EVIL ANGEL, EVOKED CURSE and GOATSODOMY.

In June 2006 Time Before Time Records released the SLUGATHOR album 'Circle Of Death', recorded by a trio of Laakso, Grönqvist and Jalas. REVEREND BIZARRE's Albert Witchfinder guested in the studio. The closing song 'Legions Of The Undead' featured lead guitar work by the late Tuomas Lintulaakso. Terranis Productions released a split 7" single, limited to 300 copies in alliance with AGE OF AGONY. SLUGATHOR donated two tracks including a cover version of TORMENTOR's 'Tormentor'.