They’ll wander around until they find suitable ruins to occupy. One way this can happen is if you make a faction into a vassal but they no longer have provinces.

Note also that vassals will still expand, but not by military conquest: only into ruins.

Notice that when a new war breaks out, all one’s vassals are automatically dragged in: they are not given an option, as they are if they are merely your allies. What this means is all the vassal’s previous wars will now be converted to peace, and all prior trade agreements cancelled. Whomever you’re at war with, they’ll be at war with, etc.

When a faction becomes a vassal, its diplomatic status will immediately mirror that of its parent state.

The following appears to be true about vassal status:

Not all factions can be made vassals regardless of how desperate they are.

The game usually doesn’t even give you the option of asking a faction to become a vassal unless you’ve really got them over a barrel: they’ve done poorly in a war against you and only have a couple of provinces left, etc. When a faction is a vassal of yours, its name appears in blue on the campaign map. Vassalage is a state whereby one faction becomes subservient to another and loses most of their diplomatic autonomy.

Total war warhammer 2 mod