The original lineup consisted of Harry Conklin on vocals (later nicknamed "Tyrant"), Mark Briody, the sole guitarist of the group in its first incarnation, John Tetley (bassist) and Rick Hilyard (drummer).

[2] The band, who were all in their late teens at the time, played at local venues in the Denver club circuit, and recorded an EP in 1983,[1] later known as Tyrants.

In early 1984, the band recruited guitarist Joey Tafolla, a native of California, and promptly recorded their first album, Ample Destruction.

[1] Without the two key members of the Ample Destruction lineup, Jag Panzer, or more accurately Briody and Tetley, as Hilyard had also been replaced by Reynold 'Butch' Carlson (who also left in 1986 along with Tafolla), revamped the band by recruiting vocalist Bob Parduba, and guitarist Christian Lasegue.

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.

[3] By 2014, Jag Panzer had commenced working on their tenth album for a near future release, also featuring lead guitarist Joey Tafolla for the first time since 1997's The Fourth Judgement.