Mutiny within the Minutemen, Preston is killed and if the player is the General there is an attempted assassination, if not than they ignore the player. All settlements in game convert to either a raider encampment, gunner base of operation, slaver group, several independent groups, and some of each of the surviving be factions, all either hostile or ambivalent to the player.
At the new settlement location the player can form their own faction however they want and be recogniZed as such in the game. A benevolent re-emergence of the Minutemen, a slaver group that trades with other settlements for free labor, a raider group that gets what it needs for survival through taking it from the weak, or a totalitarian regime bent on bringing the Comminwealth under its heel.