Cheyenne, Oklahoma in the context of Roger Mills County, Oklahoma

The Battle of the Washita River (also called Battle of the Washita or the Washita Massacre) occurred on November 27, 1868, when Lt. Col. George Armstrong Custer's 7th U.S. Cavalry attacked Black Kettle's Southern Cheyenne camp on the Washita River (the present-day Washita Battlefield National Historic Site near Cheyenne, Oklahoma).

The Cheyenne camp was the most isolated band of a major winter encampment along the river of numerous Native American tribal bands, totaling thousands of people. Custer's forces attacked the village because scouts had found it by tracking the trail of an Indian party that had raided white settlers. Black Kettle and his people had been at peace and were seeking peace. Custer's soldiers killed women and children in addition to warriors, although they also took many captives to serve as hostages and human shields. The number of Cheyenne killed in the attack has been disputed since the first reports.

Washita Battlefield National Historic Site protects and interprets the site of the Southern Cheyenne village of Chief Black Kettle where the Battle of Washita occurred. The site is located about 150 miles (241 km) west of Oklahoma City, Oklahoma, near Cheyenne, Oklahoma. Just before dawn on November 27, 1868, the village was attacked by the 7th U.S. Cavalry under Lt. Col. George Custer. In the Battle of Washita, the Cheyenne suffered large numbers of casualties. The strike was hailed at the time by the military and many civilians as a significant victory aimed at reducing Indian raids on frontier settlements as it forced the Cheyenne back to the reservation set aside for them. The site is a small portion of a large area that was declared a National Historic Landmark in 1965, and was listed on the National Register of Historic Places in 1966. The landmarked area encompasses the entire battlefield, which extends for some 6 miles (9.7 km) through the city of Cheyenne.