Great War

The Great War (not to be confused with World War I or World War II), started (and ended) on October 23rd, 2077. It is not known who dropped the first bomb, but that hardly matters. It lasted a very brief amount of time, but was unbelievably destructive. More energy was released in the early moments of that war than all previous conflicts combined.

The situation leading to the war included China invading Alaska, and the United States annexing Canada. The European Commonwealth dissolved and a world wide conflict followed when each country tried to gather what natural resources it could. This period was known as the Resource Wars.

The Great War itself began when the nukes were launched, and lasted about two hours until the world fell into darkness. Yet, the world was not completely devastated. Somehow, humanity was able to survive and eke out an existence among the ruins, establishing communities and even cities. Cities were not completely obliterated either, and some areas such as Washington DC had entirely intact buildings.

Many citizens did not heed the air raid sirens, as they figured it was just another drill. The Vaults (not including Vault 12, which was never intended to shut) sealed themselves as the Earth cooked.

A few citizens that took the air raid sirens seriously, but did not have access to vaults, made their way to various locations that they felt would be safe from the bombs, like sewers and subway stations, or in the case of the Keller Family, the National Guard Depot.

In Fallout 3, various bones that look like they could be pre-war can be found in the tunnels, along with old beds, and desks. This may imply that some citizens tried to live out their lives underground. It would explain how several above-ground communities started again, as anyone on the surface would have been annihilated by the nuclear blasts and the resulting fires and radiation.