I think I'm on the right track here I just want to clarify since I'm playing ironman. I have recently formed Italy and I am still Catholic. I invaded Tripoli, took several provinces and created the vassal of Tunisia. I now have provinces in Algeria and would like to sell them to Tunisia. However it says they are different religion. It basically looks like they are all Sunni, but Tunisia's state religion is Catholic. I guess that happened since I created Tunisia instead of vassalizing them through war or diplomacy. So do I now need to convert the Algerian provinces to Catholic to sell them to Tunisia since Tunisia's state religion is Catholic?