Thorium formed in late 1997 with a mission to play old school death metal. With members involved in other bands (Withering Surface, Iniquity, Taetre and Infernal Torment), Thorium had the experience it took to work fast and efficiently. It did not take more than a year to play the first gigs (e.g. opening slot for the reformed Artillery), record a 2 track demo and get a record deal with Diehard Music.

In the summer of 1999 Thorium entered Grieghallen Studio in Bergen, Norway with Pytten and Herbrand Larsen (Audrey Horne). Jacob Hansen (Mercenary, Raunchy, Invocator) took care of the mix. The result was "Oceans of Blasphemy"! An album released in early 2000 with overwhelming attention from the world wide metal press. Thorium was e.g. placed in the "Best Newcomers of 2000" section in Germany's Rock Hard.

Following the success of "Oceans of Blasphemy", Thorium played concerts in Denmark and was on the bill for the Nuclear Storm Festival in the Czech Republic.

Three years later the band entered the Exponent Studio in Slovakia in January 2003 with Tomas Kmet and Roman Slavik. Mastering was handled by Tue Madsen (The Haunted, Sick of it All, Mnemic). Out came "Unleashing the Demons". Again an album that received positive attention world wide. The summer of 2003 Thorium performed at the Party-San Festival in Germany and at the Brutal Assault Festival in the Czech Republic.

Since then Thorium have abandoned the sinking ship Diehard Music and the members pursued other personal projects.

it took a while for the Thorium machinery to re-activate, and in late 2005 the band recorded some promo material in the Berno Studio in Malmo, Sweden with Berno Paulsson (Deranged, The Haunted, Amon Amarth). These recordings are available on the "Cast From Hell" 7" EP released through Mughty Music sublabel Prutten Records.

Thorium released their third album "Feral Creation" on February 18 2008 via Mighty Music.