I assume there wouldn't be any in the vanilla game, but when modding would it be possible to create overlapping union tags? I.e. Union A might consist of cultures 1, 2, and 3, whilst Union B includes 3, 4, and 5 but not 1 or 2. Hopefully that example was clear enough.
I don't have the skills, the imagination or the inclination to actually do any modding myself, so the question's a little moot for me, but I thought it might raise some interesting implications
I don't have the skills, the imagination or the inclination to actually do any modding myself, so the question's a little moot for me, but I thought it might raise some interesting implications