Exhorder was a thrash/groove metal band formed in New Orleans, Louisiana during the late 1980s. They are often credited as the purveyors of the groove-oriented thrash sound later made famous by bands such as Pantera, Machine Head, and White Zombie.

Exhorder was formed in 1985 in New Orleans, USA and was one of the bands that helped shape the "Louisiana sound," a common sound shared between many metal bands from the state. They released two demos, one in 1986 called Get Rude, and another one, Slaughter in the Vatican in 1988. Exhorder split up shortly after the recording of the demo, but reformed with new guitarist Jay Ceravolo (who replaced David Main).

Slaughter in the Vatican, the band's first full-length album, was released in 1990. The album was spawned from the 1988 demo of the same name, and solidified their chugging tight riffs with a rigid structure style. Although dismissed by some because of the offensive title and front cover. Their second offering, 1992's The Law, was more so in the vein of groove metal rather than pure thrash and did not have the same effect as their debut. After their European tour in support of the album, the band split. Vocalist Kyle Thomas went on to form Floodgate with his brother, as well as briefly appearing live as the vocalist for Trouble, while guitarist Jay Ceravolo formed Fall from Grace.

Reunion

Exhorder reunited for a few reunion gigs in 2001 and 2003.

Controversy

It has long been claimed that Exhorder pioneered the angry, 90's post-thrash metal that is often linked to Pantera, as Exhorder were signed to a record label around the same time as Pantera (though Exhorder's first released their music on demos in the 1980s, while Pantera were playing glam metal music. Many have claimed that Pantera ripped off Exhorder, with the resemblance of stripped-down rhythm guitars, heavy double-bass drumming, and angry (almost identical) vocals (complimenting the basic American thrash style of the late 80's) however, Exhorder's first album Slaughter in the vatican was more in the vain of pure thrash, and Exhorder didnt introduce heavy use of groove metal techniques until they released The Law on March 15 1992, which still leaves the controversy of whether or not Pantera ripped them off or not as Pantera already had two Groove metal releases (Cowboys from hell two years before hand, And Vulgar display of power a month before hand) before Exhorder released The Law, being Exhorder's first groove metal release.

Vocalist Kyle Thomas recently claimed that while Pantera were definitely influenced by Exhorder, and may have even deliberately ripped Exhorder off, Pantera worked a lot harder for their success than Exhorder did.

source: http://en.wikipedia.org/wiki/Exhorder