Before the Great War started, Mr. House used his considerable genius and wealth to ensure that no missiles would strike the city of Las Vegas. Though a few warheads did get through in the outskirts, most of the city was spared. Despite this, the Strip itself was not re-settled until close to two hundred years after the war, at this point Mr. House began searching for the mysterious Platinum chip to rebuild the glory of Las Vegas. Sending out PDQ-88b Securitron scouts, Mr. House started negotiating with local tribes to exchange his considerable resource stockpiles for their help. Some of the tribes resisted, but three tribes eventually gained Mr. House's favor. They became the Omertas, the Chairmen, and the White Glove Society; these tribes began running the Gomorrah, Tops and Ultra-Luxe casinos respectively. (The rest were either evacuated into Freeside or killed promptly.) Because Mr. House was dedicated to restoring Las Vegas, he insisted on transforming the tribes into families with cultures that hearkened back to Vegas' glory days.
After the Great War, the Alliance stayed away from Earth for over a hundred years until it returned, and offered help to those who needed it. However, unlike the Capital Wasteland, the Mojave was more like, as one Alliance soldier said, "more like fucking Iraq than the US because of the fucking sand and raiders; I would say that this part of the US should be called Little Iraq." The Alliance has helped the New California Republic and New Vegas with spaceports, military movements, and advanced outposts and bases to house troops and refugees from the war.