Southwest Commonwealth

The Southwest Commonwealth was one of the thirteen commonwealths of the pre-War United States of America. Created in the 1969, it was comprised of the former states of Southern California, Nevada and Hawaii, and borders the Northwest and Four States Commonwealth.

Non-Mojave Nevada
Like New Vegas to the south, Northern Nevada has its own gambling haven of New Reno. Though it is officially apart of the NCR by 2281, Reno is still operated by crimes families, but only the Bishops and Van Graffs. Other than Reno there's also Vault City, a small city formed after the opening of one of the few control Vaults. This city is also a part of the NCR. There have also been many failed communities in this part of the state in the 2240s, such as Broken Hills. Once led by Marcus he went on to form and lead Jacobstown in the Mojave.

Outside of Reno and Vault City and the failed communities, there is Gecko, once led by Harold. The 80s, a roaming group of raiders, lurk the I-80 and terrorize what few small towns there are outside of the Mojave, like Caliente.

Mojave Wasteland
The Mojave Wasteland is a wasteland that comprises South Nevada. The Mojave Wasteland was having power struggles between the NCR invaders, Caesar's Legion tribals, and Mr. House. The Hoover Dam and New Vegas Strip are the main interests and concerns. Drug running and gang life had been rampant in the area, as well as runaway creatures and hostile wildlife.

New California
New California,  also referred to as the Core Region or simply California, is a loosely defined area on the American West Coast and Southwest, notable for being one of the most detailed and fleshed-out regions of the setting. New California stretches from Baja in the south to Klamath in the north. It covers most of the pre-War state of California, southern Oregon, and western Nevada as well as parts of northern Baja Mexico, and is the home of the largest post-war country, the New California Republic.

Hawaii
Aside from once being apart of the Southwest Commonwealth, there has been no significant information of the current status of Hawaii post-Great War from any released source, apart from one Thomas Davis being shipped out of there on a destroyer ship.

Southern California

 * New California (Fallout, Fallout 2)
 * Anza-Borrego (Mentioned in Fallout: New Vegas)
 * Boneyard (Fallout, Mentioned in Fallout: New Vegas)
 * Cathedral (Fallout)
 * Dayglow (Mentioned in Fallout, Fallout 2 and Fallout: New Vegas)
 * Death Valley (Mentioned in Fallout and Honest Hearts)
 * Hub (Fallout )
 * Irvine (Mentioned in Fallout: New Vegas)
 * Junktown (Fallout)
 * Lost Hills (Fallout, Mentioned in Fallout 76)
 * Mojave Outpost (Fallout: New Vegas)
 * Necropolis (Fallout)
 * Oak Creek (Mentioned in Fallout: New Vegas)
 * Owens Lake (Mentioned in Fallout: New Vegas)
 * Sac-Town (Mentioned in Fallout: New Vegas)
 * San Onofre (Mentioned in Fallout: New Vegas)
 * Shady Sands (Fallout, Fallout 2, Mentioned in Fallout 3, Fallout: New Vegas, Fallout 4)
 * Vault 13 (Fallout, Fallout 2)
 * West Tek Research Facility (Fallout)
 * The Divide
 * Ashton
 * Hopeville

Nevada

 * New California (Fallout, Fallout 2)
 * Area 51 (Mentioned in Fallout)
 * Broken Hills (Fallout 2)
 * Caliente (Honest Hearts)
 * Gecko (Fallout 2)
 * New Reno (Fallout 2)
 * Vault 15 (Fallout, Fallout 2)
 * Vault City (Fallout 2)
 * Mojave Wasteland (Fallout: New Vegas)
 * Area 2 (Fallout: New Vegas)
 * Boulder City (Fallout: New Vegas)
 * Camp Searchlight (Fallout: New Vegas)
 * Cottonwood Cove (Fallout: New Vegas)
 * Freeside (Fallout: New Vegas)
 * Goodsprings (Fallout: New Vegas)
 * Hoover Dam (Fallout: New Vegas, Van Buren)
 * Jacobstown (Fallout: New Vegas)
 * Nellis Air Force Base (Fallout: New Vegas)
 * New Vegas (Mentioned in Fallout, Fallout: New Vegas)
 * Nipton (Fallout: New Vegas)
 * Novac (Fallout: New Vegas)
 * Primm (Fallout: New Vegas)
 * Red Rock Canyon (Fallout: New Vegas)

Appearances
Fallout, Fallout 2 and Fallout: New Vegas take place in the former Southwest Commonwealth. The canceled Van Buren was to feature places in this commonwealth as well.