If we go by Fallout 3, the people in Vault 101 believe the U.S. should be habitable again by 2377, so another 100 years after Fallout 3 and the radiation should be low enough to make the majority of the continent habitable, of course that could just be a throwaway line with no truth behind it.Strazdas said:i wonder about the environments though. are the plantlife going to be regrowing now and if it takes so close to fallout 3 how its going to contrast with the grey landscape that one had.EternallyBored said:The only concrete information we have right now is from the trailer where the Mr. Handy robot Codsworth tells the main character that it's been over 200 years since the war, Fallout 3 takes place exactly 200 years after the war in 2277, so it's likely the game takes place a few years after that. So it's probably only a few years after 3 and either before or right after New Vegas. Anything more than that we'll have to wait to find out.
If I had to guess, I would say the game takes place sometime between 2277 and 2300.
The trailers for 4 also show some small plant regrowth so it looks like Bethesda is trying to increase the color palette by showing that stuff is coming back to some extent. The trees still look stripped bare, but some smaller grasses and shrubs in the trailer look like they are alive, there's even a living flower right outside the vault in the trailer. There is an area in the game where one of the bombs hit that's apparently still a blasted nuclear wasteland, but Bethesda seems to be taking some cues from the Point Lookout DLC and making it so that mutated plantlife is still around outside of the actual bomb sites.