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With the decline of the roman empire in western europe the level of urbanization and societal organization declined rapidly.

But the west recovered, new cities sprung up and states again became centralized and advanced. No large-scale decline like this ever happened again, but what if it did? Could a long time of neglect and warfare lead to larger states again collapse in Europe and be replaced by smaller local governments?

Preferably this should happen after the 17th century.
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