The band were previously known as Forbidden Evil from 1985 to 1987. Forbidden Evil became Forbidden in 1987 in order to avoid being labeled a black metal band.
Forbidden was a thrash metal band from the San Francisco Bay Area. Formed in 1985 as Forbidden Evil, the group was founded by Russ Anderson and Craig Locicero, who were both ever-present members. Since their formation, Forbidden have broken up and reformed twice with numerous line-up changes. The most recent line-up of the band comprised Anderson (vocals), Locicero (guitar), Matt Camacho (bass), Steve Smyth (guitar) and Sasha Horn (drums). Along with Death Angel, Defiance, Testament and Exodus (the latter of the two have featured original Forbidden drummer Paul Bostaph), they were one of the most successful Bay Area thrash metal bands and earned a loyal fanbase in the underground music community and critical acclaim, with their debut album Forbidden Evil (1988) regarded by critics as a classic thrash metal album and the follow-up, Twisted Into Form, as something of a masterpiece within the tech-thrash genre. Their earlier style was technical thrash metal, but the band later experimented with alternative and groove metal elements on their fourth album Green (1997).