Fallout 4 factions

Major factions

 * All four major factions can be joined in the course of the game. However, certain quests will turn factions permanently hostile:
 * Institute questline
 * Teleporting to Mass Fusion during Mass Fusion turns the Brotherhood hostile.
 * Completing End of the Line requires wiping out the Railroad.
 * Brotherhood questline
 * Taking the Vertibird to Mass Fusion during Spoils of War turns the Institute hostile.
 * Accepting Tactical Thinking turns the Railroad hostile
 * Railroad questline
 * The Brotherhood will automatically be hostile once Mass Fusion (a prerequisite for the rest of the Railroad quests) is completed.
 * Minutemen questline
 * To reach the Minutemen endgame one must make the Institute hostile, the easiest way of doing this is by killing an Institute scientist.
 * The Institute is also made hostile by completing the quest Pinned