What happens to villagers when a landmass splits?
Villagers stay exactly where they are. It is perfectly ok for a Knight to remain on a landmass which doesn’t contain a Fort. That Hovel/Town though still needs to pay the upkeep cost of the Knight though, but it just can’t produce any more Knights (as normal). However, since it is usually the case that the smaller landmass will be unable to support the upgraded Knight, he will perish anyway.