The Commonwealth (occasionally referred to as Commonwealth Wasteland) is what is left of the pre-War American state of Massachusetts in New England. While traditionally called a commonwealth in itself, before the Great War, Massachusetts was also part of the New England Commonwealth of the United States. Most of it is a "war-ravaged quagmire of violence and despair" like much of the rest of the former United States, but it is also where Boston and the mysterious Institute are located.
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