Swedish death/thrashers IMPIOUS was formed by Valle Adzic and Martin Åkesson in April ´94. The band had some difficulties finding a permanent drummer, so a friend called Johan filled in as a session drummer. Shortly after that Robin Sörqvist joined the band on bass. IMPIOUS recorded their debut demo in the summer of ´95, called "Infernal Predomination".

Shortly after the recording session drummer Johan had to quit the band due to lack of time, since he had to do the military service. To find a permanent drummer turned out to be harder than expected. No drummer was found, so another friend called Marko filled in, also just as a session drummer. So in May ´96 the band recorded their second demo, called "The Suffering", at Los Angered Recording with Andy La Rocque.

Shortly after the recording a permanent drummer was finally found! Ulf Johansson accepted the job and this was the first time the band had a full and permanent lineup. In the summer of ´97 IMPIOUS recorded their third demo simply called "Promo ´97". This demo never got to be released. At the same recording session, the band recorded a Sepultura cover for the tribute album "Sepulchral Feast". IMPIOUS covered the song "Inner Self". "Promo ´97" resulted in a record deal with Swedish label Black Sun Records, and in december ´97 IMPIOUS recorded their debut album "Evilized" in Sunlight Studios with producer Tomas Skogsberg. The album was released in the summer of ´98. Later that year in october the band entered Los Angered Recording once again, but this time to record a Metallica cover for the tribute album "Metal Melitia III". The song "One" was covered.

´99 was a quite lame year for IMPIOUS, but in January ´00 the band recorded their second album in Studio Mega with engineer Chris Silver. Unfortunately it took almost a year for Black Sun to release the album. Anyway, in the summer of ´00 IMPIOUS decieded to make some drastic line-up changes. Martin, who had always sang and played the guitar, quit playing the guitar to concentrate on the vocals. Robin switched from bass to lead guitar. And since Robin actually is a better guitar player than both Martin and Valle, this was a smart move. So, there was an empty gap to fill, and a friend called Erik Peterson was asked to join the band to play the bass. He accepted.

In March ´01 IMPIOUS recorded a four song promo in Studio Mega. The promo was sent to different labels with the intention to get a new deal. After looking at offers from some labels, IMPIOUS decided to sign a deal with Hammerheart Records (now called Karmageddon Media).

In February ´02 drummer Ulf Johansson left the band, just five weeks before the recording of the new album. No tears shed. IMPIOUS immediately braught in Mikael Norén, and in just a few weeks he learned all the 10 songs for the album. So in March ´02 the band recorded their third album "The Killer", once again at Studio Mega with Chris Silver. Also a MCD was recorded later that year, including "The Deathsquad" from the album "The Killer" plus a re-recorded version of the song "Extreme Pestilence" from "Evilized", plus three covers from Metallica, Running Wild and Mötley Crüe, and two songs from their "Promo 2001". That MCD was released in January ´03 when the band went on a European tour together with Necrophobic and Satariel. The tour turned out to be a very successful trip since IMPIOUS managed to confirm as being a very intense and powerful liveband.

In February ´04 IMPIOUS pays some respect to the fathers of death metal: Possessed, by appearing on the tribute album "Seven Gates Of Horror" together with bands as Cannibal Corpse, Sadistic Intent, Vader, Sinister, Angel Corpse and Amon Amarth. Also in February ´04 IMPIOUS also signed a worldwide deal with legendary Metal Blade Records.

During the period May-July IMPIOUS recorded their fourth album "Hellucinate" at Studio Mega, except all vocals and solos which were recorded at Valle Adzic's own Deadline Studio.