What do "regions" do?
With a recent update, counties appear to have a new property "region" (or maybe it was always there but only now it appears on the GUI).
For example, Worcester is part of "region_british_isles"[sic], which is part of "Western Europe" which is part of "Europe".
Do regions have any ingame effect?
Best Answer
It's been a while since this question's been asked, so I'm providing an updated response for anyone who comes looking for an answer to the same question, as there are actual player uses for regions in the current version of CK2.
For players who have the Jade Dragon DLC, realms in the 'far east' region can interact with China. I don't know if this one is for 3.0 or for players with Holy Fury, but a Christian controlling the whole 'near east' region can form the Empire of the Outremer.
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Formal, Functional, and Perceptual Regions: Examples included!
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