It may not be as important as the subject of slavery, but how Victoria 3 handles its geo-political landmass is just as key to the grand strategy game's DNA. Thanks to this week's development diary, we now know more about 'states' and how they fit into the game, and - more importantly - how they affect flags.
The TL;DR is that Victoria 3 differentiates between 'states' and 'state regions', the former being a dynamic political entity, and the latter being a fixed, predetermined region of the world. State regions are the primary geo-political unit, with many other mechanics such as resources, buildings etc. being defined at this level. Victoria 3's game director Martin 'Whizzington' Anward also confirmed that the number of stars on the US flag can change, depending on the number of states it owns. Whether dynamic flags is a general mechanic or a US-only one, is not known.
While the main economic and political mechanics don't concern themselves with individual provinces, the dynamic states draw their existence from these provinces. States only ever have a single owner, but their borders can change depending on how many provinces within a state region a nation controls.
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