Before the Great War, this area was home to Hopeville and Ashton: a missile base and a large city located in the Mojave Desert in Southern California. Apart from being a major element of the ballistic defense matrix, Hopeville was also the subject of a major Big MT research project concerning meteorology; a project that apparently ended in a disaster, spawning the dust storms the Divide is infamous for. Besides the project, Big MT was also a partner in different enterprises: at one point, the entire local hippie commune that protested outside Hopeville against the ongoing Sino-American War were rounded up by special riot control officers, wearing a new model of L.A.P.D. riot armor, and shipped them off to Big MT as test subjects. The whole incident was regulated by the 11th Armored Cavalry Regiment who notably wore a recognizable helmet and a more advanced riot armor.
The Great War apparently surprised the soldiers, as the ICBMs there never left their missile silos. A silence fell across the land. For two centuries the soil of the Divide lay undisturbed by human presence. However, eventually, a small survivalist community established itself in the area. Kept alive by couriers, it prospered, and more settlers moved into the new city. It prospered enough in fact, to draw the attention of the New California Republic, who began to annex it swiftly for a newly established supply line across the treacherous Divide into the Mojave Wasteland.
These actions drew the attention of Caesar's Legion, which, in its bid to take the Mojave, attempted to cut the new supply line (the Long 15 and New Canaan were the two first), sending frumentarii and assassins to explore the area after a sizeable force of legionaries struck against the Republic's forces located there. But this war did not destroy the settlement. That was the work of the Courier, who, returning to the Divide again, carried a package from Navarro by order of the NCR containing the activated ICBM detonator to the Divide, a short time before the NCR and the Legion jumped to each other's throat. When this device was close enough, it remote linked with the ICBM computers, sending a signal to the dormant nuclear missiles lying in the silos beneath the ground. They then began detonating one after another, splitting the earth, cracking and twisting the landscape, causing massive earthquakes. Entire companies of NCR soldiers in the Divide were trapped together with their Legion foes. The disaster created the Divide as it exists now: a wind-beaten maze of twisting canyons, skin-flaying dust storms and horrific abominations.
The Divide twisted the surviving NCR and Legion. As the winds flayed their skin and radiation ghoulified them, they became the marked men; skinless horrors fueled by hatred and rage for everything around them. Outside the Divide, the disaster became a blessing in disguise for the Legion: cutting off NCR supply lines along Death Valley Road and the Carson Pass Highway, it granted Caesar's Legion time to recover after their loss in the First Battle of Hoover Dam. However, it also gave birth to the greatest danger to the post-War civilization of the American Southwest: Ulysses. The Divide disaster both traumatized and inspired him as he learned the impact a single person, in this case the Courier, can have on history.
At some point after the Divide disaster, the NCR sent an expeditionary force into the Divide. However, they severely underestimated the danger of the Divide and were met with heavy resistance.  In the end, the expeditionary force was nearly wiped out by the Divide's many threats.  
Ulysses was determined to take revenge and sought to reshape the post-apocalyptic world singlehandedly, much like the Courier reshaped the Divide by unleashing nuclear fire on it. At some point before the Second Battle of Hoover Dam, Ulysses contacts the Courier via a single message: the coordinates for the canyon wreckage west of Primm, and the words "Courier Six - Ulysses", wanting to destroy their new home in his reshaping process of America before their eyes, as the Courier did for him with the Divide. The Courier answered the call and confronted Ulysses at the Divide. There, under the Old World flag and the torn skies, the two decided the fate of southwest post-War America.
The remains of a decent sized city has rendered large portions of the Divide inhospitable, thick with traps and enemies. Care should be taken when navigating these areas as players can be caught off guard. A large amount of wreckage and rubble from the military base is present early on but thins out as the player progresses. The highway is crumbled and destitute with many sections collapsed making anything more than linear exploration impossible; buildings half buried in ash and sand making the land seem dead and desolate. The northern area is utter chaos; the ground torn apart as if an open wound. The area is also swarming with marked men and deathclaws hiding in the ruins of the city. The Divide also contains multiple undetonated warheads throughout, which the player can manipulate during game-play.
- It takes three in-game days to travel between the Mojave Wasteland and The Divide.
- According to Joshua Graham, The Divide lies north of the Mojave near Death Valley but is not located in Nevada.
- Exiting and entering The Divide resets water, food and sleep counters to 0 in Hardcore mode.
The Divide only appears in the add-on Lonesome Road and as a map in Old World Blues, but the location is mentioned in Fallout: New Vegas and the add-ons: Dead Money, Honest Hearts, and Old World Blues.
Behind the scenesEdit
- Before the release of Lonesome Road, Chris Avellone's Twitter avatar showed the Divide.
- The goal of Chris Avellone when setting out to create Lonesome Road was to deliver a Zelazny-style Damnation Alley experience in the Fallout universe.
- ↑ Dialogue with Joshua Graham indicates a California location: "Something bad happened near Death Valley, at a place called the Divide. NCR couldn't cut across anymore and it slowed down their reinforcements. Terrible storms ripped entire companies apart before they even got to Nevada soil."
- ↑ The map of the Divide is located in the Big MT in Old World Blues, in the meteorological research center. Elijah mentions that Ulysses was interested in that particular facility; furthermore, it is mentioned in a terminal just outside the Y-0 research center that Hopeville was the location of an experiment gone horribly wrong.
- ↑ Chris Avellone talks about the package from Lonesome Road
- ↑ Joshua Graham
- ↑ Bravo Team mission orders
- ↑ Mission report
- ↑ Pvt. Foster's personal journal
- ↑ NCR Radio distress beacon