Jag Panzer came together in late 1981, being inspired by the onslaught of the New Wave of British Heavy Metal. The original line-up consisted of Harry Conklin on vocals (later nicknamed the "Tyrant"), Mark Briody, John Tetley who played the bass, and Rick Hilyard as the drummer. The band was known as Tyrant in its first incarnation. They soon had to change their name, because another such named band existed in California.
They saw a poster featuring a German World War II tank, named Jagdpanzer (literally "hunting tank" in German, but actually referring to what in English would be called a tank destroyer) which they decided to name their band after. They were however, unable to pronounce the name correctly and as a result, dropped the letter "D" from the name and simply called it Jag Panzer. In early 1984, the band recruited Joey Tafolla, a native of California, and promptly recorded their first album, Ample Destruction. Tafolla quit the band in 1986, releasing a solo album, Out of the Sun, in 1987, while Conklin played with Riot for a brief period in the late 1980s, before forming his own band, Titan Force. The Swedish born drummer, Rikard Stjernquist, was added to the line-up and the band proceeded to record the follow-up to their debut LP. The album was recorded in late 1987, but never got an official release.
By 1994, the band had reunited, this time with vocalist Daniel J. Conca, with Tetley and Briody on bass and guitar. Guitarist Chris Hostka and drummer Rikard Stjernquist were employed on their first official album in almost 10 years, Dissident Alliance. It was released by the German indie label, Rising Sun.
The next album was on Century Media, The Fourth Judgement, which came out in late 1997, followed by Age of Mastery (1998). Jag Panzer sought to tackle more ambitious territory for their next album, with Thane to the Throne a concept album about William Shakespeare's, Macbeth.
Mechanized Warfare was released in 2001, then the band released a double album in 2003 that featured previously unreleased tracks as well as songs from their first LP. Decade of the Nail Spiked Bat came out in 2003, and featured re-recorded and /or remixed old material. In 2004 the band released Casting the Stones. The previously unreleased Chain of Command album was remixed and was issued in 2004 as a limited edition.
In 2008, Chris Broderick left the band to join Megadeth, and was replaced by Christian Lasegue, who handled lead guitar duties on 'Chain Of Command'.
On December 23, 2008, Briody made a post on the band's official forum stating that the title of their next album will be 'The Scourge of the Light'. On the official site, the band announced that SPV/Sony planned to release the album in February 2011. The album was released March 8, 2011.
Two weeks after its release, 'Scourge of the Light' placed at #117 on the Billboard New Artist Chart, making the album Jag Panzer's most successful to date.
On July 25 2011, the band announced that they are to disband.