Is there a way to let human players choose starting territories, but force AIs to start in specific places?

I would like to set up a GoT-based diplo hybrid game, where all the players are human and all the AIs are White Walker armies. This way, the humans could negotiate and ally with each other, but not with the Walkers, who just want to murder everyone and take over the world.

Anyone know how to set something like this up?

+1

The only way to force AI's in specific places is by building a custom scenario, however I am not sure if your level is high enough to create custom scenarios