Private war at MCA?

[Marginal0]

Maybe I'm still not fully 'getting' the game yet so apologies if this is wrong info.

I have medium crown autority applied in my kingdom, and the vassals still wage private wars. The text clearly says they are not allowed to, yet a duke attacked his vassal. It may be because I recently acquired another kingdom which is also entitled to me atm and only has low crown authority, but the duke in question does not belong to the de jure or actual (current) territory of that country. So perhaps there is a bug that transforms the crown autority from one country to another.

 

[Dragnar]

Medium crown authority doesn't prevent all wars, it prevents legally declaring wars on other vassals. It's still possible for wars to happen either through revolts against lieges (which are by definition illegal and thus don't care about that being forbidden) or plots.