I joined and no, it does not remove you from allegiance to the Minutemen. Although, I haven't finished all the missions for the them so you may have to leave eventually.
English
-
Oh ok thanks !
-
same here, I joined the brotherhood but I still have the minutemen quests. also it looks like the brotherhood will control some settlements when you do missions with them, althought I don't know if they will overtake previously held minutemen settlements. .
-
Thanks !
-
I think only places with Brotherhood property like an airfield would be under BOS control.
-
The first side mission from teagan put a farm under bos control. There were no minuteman missions there so i think everything stays separate.