Formed in August 1998, the band's name is derived from the word Chimera, a monstrous creature in Greek mythology.

Throughout its history, the band had numerous line-up changes, leaving vocalist Mark Hunter as the only constant member.

Prior to Chimaira, vocalist Mark Hunter and bassist Jim LaMarca were part of a hardcore band named Skipline, which lasted two years from 1996 to 1998.

Soon after the experience, Hunter was contacted by guitarist Jason Hager, who was part of a local Cleveland metalcore band known as Ascension, to form a new group.

Hunter and Hager recruited friends and previous bandmates Jason Genaro on drums and Andrew Ermlick on bass to complete the required positions for a line-up.

[1] The band recorded a second demo that year, and it began to receive widespread airplay on several college radio stations around the area.

After landing a spot performing "Dead Inside" on the short-lived USA Network show Farmclub.com, Chimaira was signed to Roadrunner Records.

[1] Eventually, the band recorded their debut EP, This Present Darkness, which was released in 2000 via the independent label East Coast Empire and charted in the top 10 at Metal Radio.

Shortly after the release of TPD, Chimaira aligned with manager and A&R scout Thom Hazaert (who would go on to run prominent independent labels Corporate Punishment Records and THC Music), a longtime friend of sampler Chris Spicuzza, and continued to tour the US, playing consistently with bands including Hatebreed and God Forbid.

During this time, the band also contributed a cover of the Accept classic "Balls to the Wall" to the ECW Wrestling album Anarchy Rocks Vol.

Shortly after the release of the album and the tour that was to follow, Jason Hager left the band when he discovered he was going to become a father.

Released October 2, 2001, Pass out of Existence would also feature a guest appearance from Deftones' guitarist Stephen Carpenter on the track "Rizzo".

[2] In addition, a portion of the band's fanbase reacted negatively to the album, partly because of its cleaner, more polished production compared to This Present Darkness.

Going on advice from Slayer guitarist Kerry King, Hunter contacted Kevin Talley, an experienced death metal drummer who had previously been in the bands Dying Fetus and Misery Index.

The self-titled album, the first (and only) one featuring Talley, was released in August 2005 while the band was taking part in the inaugural Sounds of the Underground tour.

Hunter and DeVries also participated in another musical project that year, Roadrunner Records' twenty-fifth anniversary CD entitled The All-Star Sessions.

The only downside of this happy event was that the band decided to call off the Eastpak Antidote tour with Soilwork, Sonic Syndicate and Caliban.

[needs update][8] Also in March, Chimaira released a cover of The Troggs' "Wild Thing" as a single on YouTube and iTunes,[9][10] in response to the "Charlie Sheen phenomenon".

[11] On April 5, 2011, keyboardist and programmer Chris Spicuzza announced he would be leaving the band (a decision he made in January), citing a "negative environment" and the general state of the music industry.

On May 28, at Peabody's in Cleveland, OH, the new album was revealed to be titled The Age of Hell that was met with the debut live performance of the song "Trigger Finger", which will be included on the record.

It was confirmed that Emil Werstler will be replacing Rob Arnold as the lead guitarist, meanwhile Matt Szlachta from Dirge Within[15] and Jeremy Creamer from Dååth will be handling rhythm guitar and bass duties respectively.

[20] On June 21, 2017, ThePRP.com announced that a one-off reunion of the band's "classic" lineup would take place on December 30, 2017, during the group's Chimaira Christmas event, which would be seven years since this line-up performed together.

Arnold also said that there was discussion of putting together new music, that riffs had been passed around but no full songs had been completed and there were no immediate plans to record or release a new album.

[23][24] On December 13, 2022, the band announced two reunion shows to take place in May 2023 to celebrate the 20th anniversary of The Impossibility of Reason.

[25] Five months later their Instagram account posted an image of the band's logo with "XXV" in the middle,[26] potentially hinting at a 25th anniversary event.

The band announced performances for 2024 at Inkcarceration Fest, their first festival concert in 14 years,[27][28] and Headbanger's Boat, headlined by Lamb of God.