In the December of 2012, on the winter solstice, a date prophesied by the Mayans as the end of evolution, a date prophesied by Nostradamus as World's End, man chose to evolve by the process of natural selection through self extermination from nuclear fallout. The decade long year War on Terror escalated to a series of short events between many warring nations that ravaged the known world on all sides in 24 short hours forcing man into an Exodus that would last 20 years for the chosen survivors, before they could return to the ruins of civilization and start a new era of man. The survivors are the lucky ones, the people that made it to fallout shelters, and those that somehow survived against all odds.
Exodus: Post-Apocalyptic Roleplaying was originally known as Fallout Pen and Paper. Licensed in the Fallout universe, but due to legal complications with Interplay and Bethesda Softworks, Fallout's current copyright holder, the publisher decided to continue working on the game, retaining most of its elements while excluding all references to Fallout.