Legion is set in the modern United States. The adventure is set six months after the demons appeared on the west coast, about May or June of 2013.
In December 2012 what is refered to as “The Rapture” by some religions occured in the United States. Many people vanished into thin air and everyone else was just left behind. Very shortly after multiple cities on the west coast had reports of cretures attacking them. The remaining police and military forces responded the best they could, but more and more of these creatures appeared. After a week of fighting creatures that looked like men with wings carrying swords few into the cities and started battling back the evil creatures. It became known later that these were demons and angels. The fight lasted for weeks, destorying most of these cities in the process, but the angels eventually retreated.
The angels retreated back to the east coast and there was immediatly discussion from the U.S. government about what to do. Heated debates went on for days. The leader of the angels in North America, the Archangel Michael, explained what was happening to the remaining humans. He explained he was the commander of the Army of God and that the other creatures were demon. He refered to them as The Legion. He informed everyone that this was the final battle over Earth. The government eventually agreed to side with the angels and offered their full support.
Little has happened since then. There seems to be a break in the conflict as both sides consolidate their forces.
After the demons appeard angels appeard and a large battle began, but the battle soon ended and each side became entrenched on their own side. The demons razed the west coast and up to the Rocky Mountains. The angels are on the east coast and control up to the Mississippi River. The mid-west Great Plains area is a sort of no-man’s-land. No side has control over it and it has been left relatively uncontested. Many human settlements still exist there and some people refuse to leave. These settlements are often walled and guarded to the best of the occupant’s ability. Other towns have been destoryed by demons or raided by bandit clans.
Other countries may or may not have experienced the same events. Only “Christian Nations” experienced the Rapture. Other nations experienced their own end times prophecies and different events unfolded, but that is out of the scope of this adventure. The main point is that not all ares had the same end.