By the way, the best solution when there were clearly two or more cultures in a province is to add province modifiers representing all of them.
When a province's owner is Turkish, the Turkish culture can become predominant, and the province culture becomes Turkish: but the Greeks and Armenians are still there in the province modifiers. If the province changes hands to a Greek ruler, its culture can flip by event to Greek: but the Turks … You get the idea.
Something basic like this is easily doable (by Paradox, if they felt like it, just as much as by modders). Province Culture itself is really just another province modifier, just one displayed in a different way and that gets certain special treatment in the engine code.
Edit: The Dei Gratia mod already does this on a huge scale, but for religious, not cultural, minorities. However, to represent a specific regional cultural situation rather than all world religions, you would not need anything like the amount of DG's code.
When a province's owner is Turkish, the Turkish culture can become predominant, and the province culture becomes Turkish: but the Greeks and Armenians are still there in the province modifiers. If the province changes hands to a Greek ruler, its culture can flip by event to Greek: but the Turks … You get the idea.
Something basic like this is easily doable (by Paradox, if they felt like it, just as much as by modders). Province Culture itself is really just another province modifier, just one displayed in a different way and that gets certain special treatment in the engine code.
Edit: The Dei Gratia mod already does this on a huge scale, but for religious, not cultural, minorities. However, to represent a specific regional cultural situation rather than all world religions, you would not need anything like the amount of DG's code.