Southwest Commonwealth Conservation Area

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

The commonwealth bordered the Northwest Commonwealth, the Four States Commonwealth, and the country of Mexico.

New California
New California is a region defined by the presence of the New California Republic, which is comprised of the entirety of California as well as areas of northern Nevada, southern Oregon, and Baja California, Mexico. By 2281, the region is dominated by the NCR.

Former Southern California
Also known as the Core Region, and formerly known as southern California. The city of San Diego was damaged during the war, with its inhabitants eventually leading an exodus to the ruins of Los Angeles, now known as the Boneyard. Located in between is "the Glow," the ruins of a West Tek research facility. Junktown, the Hub, and Shady Sands make up the northern part of the region.

By 2281, the region is dominated by the NCR, which controls a large portion of southern California. Its borders stretch south into Baja, up into northern California, and east into Nevada and Arizona.

Former Nevada
The former state of Nevada is desolate. Few are able to traverse the rough terrain of the Sierra Nevada Mountains alone. The region is sparsely populated. New Reno is the most significant town of northern Nevada, with smaller settlements such as Vault City, Gecko, and Broken Hills dotting the map.

The Desert Rangers operated out of Nevada, as well as Utah and Arizona. Caesar's Legion would eventually push them out of the Grand Canyon and into Nevada. They would go on to become assimilated into the New California Republic in exchange for protection against the Legion.

Mojave Wasteland
The Mojave Wasteland is a region comprised of southern Nevada, as well as parts of California and Arizona. In 2274, the NCR sent scouts to the region and discovered the ruins of Las Vegas and an intact Hoover Dam. Plans were made to occupy the dam, and restore it to a working order to provide the NCR with power. The enigmatic Mr. House saw the arrival of the NCR as an opportunity and sent his securitrons to the tribes inhabiting the ruins - offering supplies and materials in exchange for their service.

Three tribes accepted this deal, forming what would be the Three Families, with each group running their own casino on the Strip. When the NCR returned in force to the Mojave, they found securitrons and the Families already occupying the dam. The New Vegas Treaty was signed, with the sovereignty of New Vegas recognized and guaranteed by the NCR, while the NCR would take full control of the Dam, with 5% of its power being routed to New Vegas.

In 2277, Caesar's Legion arrived in force to take the region - leading to the First Battle of Hoover Dam. The Legion ultimately lost the battle with the Malpais Legate, who led the Legion forces, set on fire, and thrown into the Grand Canyon as punishment. The war then ground to a stalemate as both sides shored up their forces on either side of the Colorado River until the Second Battle of Hoover Dam in 2281.

The Divide
A region on the border of California and Nevada. Before the war, the area was the site of numerous nuclear missile silos and the Big MT complex's scientific experiments. A small trading community formed in the pre-War towns of Hopeville and Ashton, and was beginning to thrive. The NCR-Legion War came to the region, as the Divide proved a crucial transportation route for NCR troops to the Mojave. The Legion, in turn, sought to cut off the NCR's transportation circuit.

The battles would be all for naught, as a courier unintentionally brought a nuclear detonator recovered from the Enclave at Navarro. The detonator set off the still dormant nuclear missiles underground, destroying the region with earthquakes, radiation, dust, and sandstorms that could skin a man alive. Both the Legion and the NCR were forced to abandon the forces they had in the region.

Joshua Graham mentions this situation and the state of Nevada by name when describing to the Courier how the New California Republic used to be able to bring reinforcements into the Mojave via State Route 127. He explains the storm in the Divide cut the NCR supply lines, making the NCR unable to travel north to get around the mountains into Nevada.

Former Hawaii

 * Before the war, a military presence existed in the state, from where destroyer ships were deployed and was a destination for aviators.
 * Vault dwellers will occasionally mention Hawaiian style pizza.

Appearances
The Southwest Commonwealth appears in Fallout, Fallout 2, Fallout: New Vegas and its add-ons, as well as the Fallout Bible. It is mentioned in Fallout 3, Fallout 4 and its add-on Far Harbor, Fallout 76, and Fallout Shelter. The pre-War iteration of the Fabulous New Vegas sign appears in the Atomic Command Pip-Boy game. The Southwest Commonwealth was also to appear in Van Buren and Jason Mical's Fallout Pen and Paper d20.