The main story takes place in the year 2277, around 36 years after the events of Fallout 2, of which it is not a direct sequel. It takes place within Fallout 's usual setting of a world that deviated into an alternate timeline thanks to atomic age technology, which eventually led to its devastation by a nuclear apocalypse in the year 2077 (referred to as the Great War), caused by a major international conflict between the United States and China over natural resources and the last remaining supplies of untapped uranium and crude oil.

The game is set within a post-apocalyptic, open world environment that encompasses a scaled region consisting of the ruins of Washington, D.C., and much of the countryside to the north and west of it, referred to as the Capital Wasteland. It was released worldwide in October 2008 for Microsoft Windows, PlayStation 3, and Xbox 360. The game marks a major shift in the series by using 3D graphics and real-time combat, replacing the 2D isometric graphics and turn-based combat of previous installments. The third major installment in the Fallout series, it is the first game to be developed by Bethesda after acquiring the rights to the franchise from Interplay Entertainment. Fallout 3 is a 2008 action role-playing game developed by Bethesda Game Studios and published by Bethesda Softworks.

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