They are essentially the same people, yet they see and introduce themselves differently. The Reangs have integrated quite well in Tripura's society to the point where they don't see themselves as outsiders and they aren't seen as outsiders by other people either. The Brus and Mizos haven't done much integration. They live in closed neighborhoods and have a rather hostile relationship with each other. Understandably given their history, the Brus will identify themselves as Brus nothing else so will the Mizos. Thus ethnically they maybe the same but their self image, worldview and religion more often than not are very different.They are the same people.. What are you suggesting?
Due to this hostility and different levels of assimilation to our society they are identified differently in both Tripura and Mizoram.