The Fort Peck Indian reservation is located in northeastern Montana. It was established in 1871 to serve the Assiniboine and Sioux Indians. The Fort Peck Reservation boundaries encompass 2.09 million acres of which only 378,000 are tribally owned trust land. The Fort Peck Assiniboine and Sioux Tribes have an enrollment of approximately 10,600 members. About 62% of those tribal members currently live on the reservation. Assiniboine tribal members tend to reside on the western portion of the reservation, centered in the towns of Oswego, Frazer and Wolf Point. Sioux tribal members, on the other hand, tend to reside on the eastern portion of the reservation, centered in the towns of Poplar, Brockton, Riverside and Fort Kipp.

History of Frazer School
   
    In 1906, day schools were built in Oswego, Riverside, and Milk River. Later in 1927, a dozen freshmen enrolled in the new high school which was located a half a mile southeast of Frazer. It was moved into town in 1928. In 1932, both the grade school and high school were combined into a new building. In 1933, Frazer held its first District Basketball Tournament.