Marias Massacre in the context of Montana Territory

Mountain Chief (Blackfoot: Nínaiistáko or Ninna-stako; c. 1848 – February 2, 1942) was a South Piegan warrior of the Blackfoot Tribe. Mountain Chief was also called Big Brave (Omach-katsi) and adopted the name Frank Mountain Chief. Mountain Chief was involved in the 1870 Marias Massacre, signed the Treaty of Fort Laramie in 1868, and worked with anthropologist Frances Densmore to interpret folksong recordings.

Eugene Mortimer Baker (July 7, 1837 – December 19, 1884) was a major in the United States Army, and served as an officer in the 2nd Cavalry Regiment in the Western Territories of the United States. He is most known for his role in the Marias Massacre in early 1870 and from the lack of discipline he faced following the event.

President Ulysses S. Grant sympathized with the plight of Native Americans and believed that the original occupants of the land were worthy of study. Grant's Inauguration Address set the tone for the Grant administration Native American Peace policy. The Board of Indian Commissioners was created to make reforms in Native policy and to ensure Native tribes received federal help. Grant lobbied the United States Congress to ensure that Native peoples would receive adequate funding. The hallmark of Grant's Peace policy was the incorporation of religious groups that served on Native agencies, which were dispersed throughout the United States.

Grant was the first President of the United States to appoint a Native American, Ely S. Parker, as the Commissioner of Indian Affairs. After the Piegan massacre, in 1870, military officers were barred from holding elected or appointed offices. During Grant's first term, American Indian Wars decreased. By the end of his second term, his Peace policy fell apart. Settlers demanded to invade Native land to get access to gold in the Black Hills. The Modoc War (1872–1873) and the Battle of the Little Bighorn (1876), were detrimental to Grant's goal of enforced Native assimilation to European American culture and society.