Final answer:
In "The Buffalo Dance," the conflict between the two tribes is caused by the clash between the Plains Indians' religious beliefs and the attempts of Easterners to assimilate them.
Step-by-step explanation:
In The Buffalo Dance, the conflict between the two tribes is caused by the religious beliefs and practices of the Plains Indians. The buffalo holds a central role in the sacred earth and many tribes celebrate the bison through ceremonies like the Sun Dance. These religious beliefs clash with the attempts of Easterners to assimilate the Plains Indians and disrupt their way of life. The conflict escalates when the Army perceives the ghost dance and buffalo dance ceremonies as signs of impending warfare and takes action to stop them.