Tiamat is a Swedish metal band founded near Stockholm in 1990 and led by Johan Edlund. To date they have released ten studio albums. The band went through a number of stylistic changes in their earlier releases before settling on gothic metal. Under Edlund's leadership, the band would modify their style with influences ranging from Black Sabbath, Mercyful Fate, Candlemass, Pink Floyd and King Crimson combined with Sumerian lyrical themes. H. P. Lovecraft's writings also appear to have influenced Tiamat's thematology, a development consistent with a broader trend in death metal culture.
The band was formed as a four-piece under the name Treblinka in 1987. Using pseudonyms they released the single "Severe Abomination" in 1989. After having recorded the album Sumerian Cry in 1989, guitarist/vocalist Johan Edlund and bassist Jörgen Thullberg parted ways with the other two founding members who formed the band Expulsion. They subsequently changed the name to Tiamat, after the Babylonian goddess representing the primordial sea and forebear to other gods. The Sumerian Cry album included re-recorded Treblinka songs and was released in June 1990.
Edlund recruited Thomas Petersson on guitars and Niklas Ekstrand on drums and signed the band to Century Records. They started the recording process in the middle of 1991, beginning a lengthy collaboration with the polish guitarist Waldemar Sorychta would produce and contribute instrumentation to many of the band's albums.
1994's critically acclaimed Wildhoney mixed raw vocals, slow guitar riffs and synthesizer sounds which sounded different from other extreme metal bands active at that time. An almost continuous 40-minute piece of music, Wildhoney led to the band's appearances at the Dynamo and Wacken Open Air metal festivals in 1995. The group would play a second gig at Dynamo two years later.
Upon the release of A Deeper Kind of Slumber in 1997, Edlund relocated from Sweden to Germany and declared himself the only permanent member of the band; all albums that would follow would cement the band into a more gothic metal/rock sound, quite different from the extreme music they did in the years before.
The band signed to Nuclear Blast in June 2007, and released their ninth album Amanethes in April 2008. In August of that year, Thomas Wyreson announced that he was quitting the band, stating that "it's just kinda hard to make everything work with the family etc."
Their song "Cain" was featured in the 2004 video game '.
The band's tenth full-length studio album, The Scarred People, was released in November 2012 through Napalm Records.
When they were still named Treblinka, the band played raw black/death metal. Early Tiamat albums like The Astral Sleep and Clouds explored death-doom, before the band shifted towards a more gothic and atmospheric sound on Wildhoney (1994) and beyond, with later albums showing a Sisters of Mercy and Pink Floyd influence.