Upon resolution of the war/migration.. the active player can..
.. start a civilization on ANY unoccupied continent.
.. select a follower of ANY active civilization.. including the same follower used to pay for the war/migration.
If neither option is available.. the active player draws a tile and ends his/her turn.
I am confused, I can't find this anywhere in the rules. That would seem extremely powerful - sacrifice a follower -> start war / migration -> resovle war / migration -> pick up follower that was just sacrificed or other follower of your choice.