The Blackfeet tribes have called the northern Great Plains home for thousands of years. In the 1800s, American settlers began moving to the region, renaming it "Montana Territory." Despite thriving trade and the prevalence of male settlers marrying Indigenous women, tensions often flared into violence. On the morning of this day in 1870, the U.S. Army opens fire on a camp of Piegan Blackfeet while Chief Heavy Runner waves a signed agreement promising Army protection. The commanding officer is reportedly drunk. Troops slaughter 173 or 217 unarmed women, children and elderly, and set fire to the camp. When asked for an interview about the massacre, U.S. Army scout Joe Kipp refuses, saying the military would hang him if he told people what he knew.