Rancid is an American punk rock band formed in Berkeley, California in 1991. Founded by Tim Armstrong and Matt Freeman, former members of the band Operation Ivy, Rancid is often credited as being among the wave of bands that revived mainstream interest in punk rock in the United States during the mid-1990s. Over their 31-year career, Rancid retained much of its original fan-base, most of which was connected to its underground musical roots.