When happiness drops too low in a settlement it will renounce allegiance to the player and any factions associated with him. They see you as incompetent and dangerous making insufficient bed numbers or whatever they angry about.


They will turn hostile and will remain hostile. Even your turrets will turn on you if they arent connected to a terminal (Which is passworded obviously)

To regain settlement you must cleanse the population and start fresh.


Sanctuary hills mutiny is the same except all essential npcs will be on your side and not be angry at you. They will actually fight the settlers.



Settler assistance


Settlers can be companions and can take many with you. To prevent the game becoming overpowered their hp is considerably reduced the more followers you have. So a party of 12 followers will lose people fast so realistically to be of much use maybe only take a small teammof 3-4 and your companion of course if you want.


This means more numbers wont make gameplay any easier but will allow people to roam with big parties because it is fun.