Enclave

The Enclave is a militaristic organization, directly descended from the pre-War United States government and military industrial complex that claims to still have authority over the ravaged country. It is composed mostly of the descendants of government officials and military officers with ties to powerful corporations who retreated to a Poseidon Energy oil rig when the Great War started. They generally consider most people born outside the Enclave to be mutants fit only for eradication.

However, isolated Enclave shards e.g. in the Midwest do not follow the general modus operandi of the Enclave, instead aiming at truly rebuilding the United States, rather than eradicating perceived mutants. These are mostly made up of doctors and scientists. Arcade Gannon came from one of these shards.

The Enclave takes pride in being one of the last bastions of pure strain humanity left, aside from the unopened Vaults. Because of the effects of radiation and the Forced Evolutionary Virus on the people of the Wasteland, members of the Enclave generally do not consider them to be human any more, even if they look no less human than they do. They, as well as other mutated creatures, like super mutants and ghouls, are considered to be sub-humans that are at best to be used as slaves, and at worst eradicated so that "true humanity" could take their place as the real nation of America.

The Enclave's government and armed forces structures mirror that of the pre-War United States government and the U.S. Army. The government is headed by the President, and according to some speeches made on Enclave Radio there is still some form of Congress. The Enclave's scientists continue to do research on armor (e.g. the Advanced Power Armor) and weapons after the War and thus have even better equipment than the Brotherhood of Steel, who only have U.S. Military standard issue left over from when the Great War broke out. The Enclave also has access to one of the last supplies of fossil fuel in the world and the advanced Vertibird helicopters.

One of the few old world organizations to survive the Great War, the Enclave was once the shadow government of the United States. Members of the Enclave both embraced the idea of a nuclear war and knew that the common man could not survive it. They believed that as long as the "important people" of the United States survived, they could regroup quickly and wipe out communism once and for all. Though not technically part of the Enclave, many powerful corporations benefited from the Enclave's actions and their research facilities were protected during the "firestorm" of 2077.

In 2073, as the global race to exploit the handful of remaining natural resources reached its fevered peak, the United States managed to stake a claim on the world's last known supply of crude oil, buried thousands of feet beneath the Pacific Ocean.

Poseidon Oil, a major U.S. energy concern, was contracted to build an oil rig and extract the oil. Before long, the oil ran dry and it was abandoned by Poseidon.

Come 2077, with total nuclear war rapidly arriving at America's doorstep, the President of the United States and a number of other United States government officials left their posts to take refuge in a number of secret locations around the world. Among them was the Poseidon oil rig. Here, the President himself set up a secret base from which the USA could continue to exist and wage war on China, with the eventual goal of retaking the continental United States. The Vault Experiment Program

The Vaults were funded by the U.S. government and, accordingly, the government had control over them. Ostensibly, they were intended to allow a selection of privileged United States citizens to survive the Great War. Secretly, however, a large part of the Vault Project had a far more sinister goal. The U.S. government's real plan to survive a nuclear war was simply to find another planet to live on after blowing up this one. A spacecraft designed to ferry the human race to another planet was either under construction or ready to go before the War. The plan was for the government to flee to the oil rig, and then leave in a spaceship for another planet the Enclave (?) or other personnel responsible for safeguarding the bloom field space center had either been ordered off of, taken to safe locations, or simply abandoned the space center. .

Any voyage to space would have been very difficult and fraught with unforeseeable complications. Thus, to test the aptitude of the average American person to travel to another planet, many of the Vaults were designed to have some sort of critical flaw. Vault 12, in Bakersfield (better known as the Necropolis), had a faulty Vault door that wouldn't close all the way, allowing dangerous radiation to leak in, leading to the creation of California's ghoul population. Vault 15, which is a few miles east of Vault 13, was built normally (the rockslide that buried its control center was accidental), but it was populated with a diverse mix of races and people to see what sort of tensions arise when varied backgrounds are packed into a small environment. Vault 13, the home of the Vault Dweller in Fallout, was intended to stay shut for a full 200 years to test the effects of long term isolation (the troubles with the water chip forced the Overseer to improvise, potentially ruining the experiment as much of the Vault's population left to found Arroyo). The types and purposes of the experiments go on. Vault 8 (which is the Vault that Vault City was built around) was a control group, a Vault intended to exist normally to serve as a reference point for the other Vaults.

In order to monitor the populations being experimented upon, the Enclave's oil rig possessed a great deal of equipment that allowed them to observe and control the Vaults. For example, the Enclave sent the all clear signal to Vault 8 shortly after the War, prompting them to leave their Vault and build their city. These monitoring tools also let the Enclave see that the population of Vault 13 was largely intact. Thus, they traveled in force to Vault 13 and sent a command to the Vault's computers to open the Vault door. After taking care of some mild resistance, the Enclave troops rounded up the residents of Vault 13 and shipped them off to the oil rig in Vertibirds to take part in the Chemical Corps' FEV experiments.

Eventually, due to either a change of plans by the Enclave's leadership or the spacecraft being destroyed, the Enclave abandoned their initial goal of settling on another planet, and decided to resettle the one they already had, although the Vault monitoring and research continued (as the Vault Behavioral Project Dr. Henry mentions). Rise to power

For a long time after the Great War, the Enclave sat quietly in its oil rig, consolidating its forces and working on gaining a technological edge over anyone on the mainland. Eventually, though, when they felt it would be safe, they decided it was time to move out and start working towards the rebirth of America. Using their rather impressive Vertibirds, the Enclave sent out scouting parties all over California, the closest state to the oil rig.

What they found there scared them considerably: mutation was rampant. The Enclave scouting parties arrived in California after the Master's defeat, and so saw super mutants and ghouls littering the land and the destruction and ravages they caused. When this was reported to the higher ups at the Enclave, it was decided that all the mutants would have to go. It occurred to the Enclave that those who had lived out in the open on the mainland for over a hundred years since the end of the war must have been contaminated or compromised somehow by radiation...or worse (indeed, most people living in the Wasteland were inoculated with an airborne mutation of FEV immunizing them to the full effects of the real serum). These mutants too, then, would have to be destroyed before true humanity, true America, could once again lay claim to the mainland.

Reconnaissance and exploration of California continued: the Enclave didn't have any means of carrying out their genocidal ambitions short of destroying the world all over again with nuclear weapons. Eventually, Enclave troops stumbled across the old abandoned Mariposa Military Base, where research on the Forced Evolutionary Virus had been done before the Great War. The FEV was what created the super mutants that most threatened the Enclave, and it would eventually come to be the Enclave's solution to these same mutants.

The Enclave excavated the military base, largely using slave labor gathered from the nearby mining town of Redding, eventually finding the vats deep inside the lower levels of the base. Though they had been buried in rock and forgotten for decades, the vats still contained that old familiar green bubbling gunk, the Forced Evolutionary Virus. The Enclave gathered samples to be sent back to the oil rig for further analysis. Before long, though, the slave miners, some being fully exposed to raw FEV, others likely falling into the vats accidentally, began to mutate into a second generation of super mutants. The mutant slaves soon overthrew their guards. Seizing their weapons, hardware left behind by the first mutant army or anything lying around, the super mutants stormed the upper levels and quickly overran the troops in the base. Panicked and retreating, the Enclave troopers on the upper levels fled the base and used explosives to seal the entrance, trapping the second generation mutants inside the base. The Final Solution

Even though things went badly at Mariposa, the Enclave still had the samples of FEV they needed. Back at the oil rig, the United States Chemical Corps began work on the serum immediately. They found that it would be possible to make from FEV an incredibly potent and lethal toxin. But, in order for research to progress, they would need test subjects. They needed two test groups: one of clean, pure humans and another composed of the "mutants" that lived all over the mainland, suffering radiation and FEV exposure for decades that, to the Enclave, made them unclean. The unclean sample was easily obtained by kidnapping the entire population of Arroyo.

The clean group would be more difficult to obtain though. The Enclave wouldn't allow the Chemical Corps to use people living on the oil rig (presumably because they were all too important to the Enclave's various projects). So, they had to look elsewhere. Once again, the mainland provided the needed stock. The stock source turns out to be the residents of Vault 13, the "Control Group", as President Richardson puts it. Before long, the Chemical Corps developed their supertoxin. It was found to be 100% lethal to tainted humans. Fall and Aftermath

Just as the Enclave was preparing to launch the poison into the jet stream to kill the entire population of the mainland, a tribal known as the Chosen One arrived at the oil rig on the Poseidon oil tanker that had sat in San Francisco for years. The Chosen One freed the survivors of both the Vault 13 population as well as the Arroyo tribals and started a self-destruct sequence in the oil rig that destroyed the entirety of the Enclave's headquarters, saving the world from horrible death at the hands of the mutant FEV.

The apparent destruction of the Enclave erased all trace of President Richardson from history. Now the title of "President" is used there simply as a bogeyman to frighten children. However, the destruction of the oil rig did not cause all of Enclave to be destroyed, as Navarro and other, smaller outposts on the mainland were able to survive. Resurgence

The Enclave was not destined to die with the oil rig. Remaining West Coast Enclave forces, under the command of Colonel Augustus Autumn's father rallied to the command of a new, enigmatic President, John Henry Eden, and rallied to the facility of Raven Rock on the East Coast. Unbeknownst to anyone but Autumn's father and later Autumn himself, Eden was in fact a ZAX super-AI developed by the Enclave in the pre-War period to allow the government to be continued in the event of disaster, and had achieved self-awareness and direction. Previously employed as Presidential adviser and Raven Rock administrator, Eden took command of the East Coast Enclave forces. For a further thirty years, the Enclave stayed shut up in Raven Rock, only sending out Eyebots to scout the wastes and transmit Enclave Radio to the denizens. Meanwhile, Eden formulated new procedures to help usher in his vision of a new America:

   Mission Directive: Establish and enforce Enclave presence among general populace, disposal of genetic non-compliance offenders.
   I. Establish constituency enforcement point at coordinates 39.138 x -77.070. Monitor civilian movement in area, and debrief superior regarding any events of notable significance or regularity.
   II. Distribute purified water rations to civilians willing to submit to genetic compliance screening. Participation in screening is compulsory for all civilians, and use of force is authorized in enforcement.
   III. Genetic non-compliance offenders should be detained at checkpoint.
   IV. To conserve consumption of Enclave resources, detainees should be disposed of by flame only when withholding facility becomes overcrowded, or detainees become unmanageable, whichever comes first.

Sources:

   * Fallout Bible
   * J. E. Sawyer's PnP
   *[url=http://fallout.wikia.com/wiki/Enclave]Fallout Wiki[/url]