Part 31: Brutus Salad Explains Invasion Mechanics
Kersch posted:
Update 14: War for the French Crown 1250 - 1253
Kersch posted:
Part 10: Invasion 1203 - 1215
Well let’s look at a screen from earlier in LP

Look at that second effect if Kersch successfully invades Norway, “Takes all occupied titles form King Einar”, this is a very deceiving sentence as it sounds like you’ll only get Holdings that King Einar directly holds. This is not the case,you get any county that you occupy with the Invasion CB. So If I’m William of Normandy and I occupy this:

I will get this as my direct demesne.

What this effectively means is that you can completely remove any vassals to the former king of whatever country you’re invading and replace them with friends/sons/ inbred idiots if you want.
On the flip side this can be used to completely fuck over an invading force*. If I’m Harold Godwinson and I surrender to William early in the war:

Then he gets all of one county for his trouble.

Additionally since he’s not of the same culture and was just recently at war with his new vassals , it’ll be all of six months before they rebel and put me, Harold Godwinson back on the throne again.
*Just one minor note: I’m fairly sure the ‘Tribal invasion’ CB that the Il Khanate, Golden Horde and Timurid Empire get will take all your lands if you surrender regardless of how much the invader has occupied, so you probably will not want to surrender right away if you are fighting Mongols.