Firestorm has been described as a landmark release in hardcore punk for its metal influences and political, militant lyrics, along with helping "pioneer what would become both a signature sound for the band, as well as metalcore as a whole – right alongside the likes of Integrity.

After recording Earth Crisis' debut EP, All Out War (1992), drummer Mike Riccardi was unable to commit himself to touring and was replaced by Dennis Merrick.

[6] Vocalist Karl Buechner had, by the time of the deal, been two years in college with the intention of becoming a history teacher, but ultimately left it to focus on his music career.

[8] In the summer of 1993, at the beginning of the national All Out War tour, Earth Crisis recorded Firestorm with music engineer Bill Korecky in his Mars Studios (Cleveland, Ohio).

The band recruited a temporary bassist with the requirement that he has to be vegan straight edge, but after realizing that the player was not as good as they expected, Crouse and Read recorded the instrument.

[13][2] "Firestorm", the first track, starts with E open chords and "a focused, unrelenting tone" which anticipates the arrangements of "extended mosh parts" during the EP.

[12] Vocalist Karl Buechner said that he composed it following the drug-fueled crimes and violence that escalated through the first half of the 1990s in northern Syracuse, where his nephew, girlfriend and previously himself had lived.

[28] Several authors describe Firestorm as a landmark release in hardcore punk for its introduction of metal elements and militant eco-political lyrics, which in turn inspired numerous bands.

[38] In retrospective interviews, Propagandhi vocalist Chris Hannah expressed admiration for the uncompromising animal liberation message of Earth Crisis and the vegan straight edge scene.