The Oakland firestorm of 1991 was a large suburban wildland–urban interface conflagration that occurred on the hillsides of northern Oakland, California, and southeastern Berkeley over the weekend of October 19–20, 1991, before being brought under full control on October 23. The official name of this incident by Cal Fire is the Tunnel Fire. It is also commonly referred to as the Oakland Hills firestorm or the East Bay Hills fire. The fire ultimately killed 25 people and injured 150 others. The 1,520 acres destroyed included 2,843 single-family dwellings and 437 apartment and condominium units. The economic loss from the fire was estimated at $1.5 billion.

Oakland is the most populous city in and the county seat of Alameda County, California, United States. A major West Coast port, Oakland is the largest city in the East Bay region of the San Francisco Bay Area, and the third-largest city overall in the Bay Area. With a population of 440,646 in 2020, it serves as the Bay Area's trade center: the Port of Oakland is the busiest port in Northern California, and the fifth- or sixth-busiest in the United States. A charter city, Oakland was incorporated on May 4, 1852, in the wake of the state's increasing population due to the California gold rush.