Thomas Mower McDougall subsequently he was appointed Captain, 15 Dec 1875. In 1876 Captain McDougall commanded Company B and accompanied the 7th Cavalry Regiment, under command of Lt. Col. George A. Custer in its fateful departure from Fort Abraham Lincoln to participate in what became known as the Great Sioux War of 1876, which culminated in the Battle of the Little Bighorn, also known as Custer's Last Stand which occurred on June 25–26, 1876. On May 17, 1876, the 7th Cavalry left their base at Fort Abraham Lincoln near present day Mandan, North Dakota to join in a campaign against the Sioux Indians.
Battle of the Little Bighorn Riley, Kansas, during which time it fought one major engagement and numerous skirmishes, experiencing casualties of 36 killed and 27 wounded. Six other troopers had died of drowning and 51 in cholera epidemics. In November 1868, while stationed in Kansas, the 7th Cavalry under Custer had successfully routed Black Kettle's Southern Cheyenne camp on the Washita River in the Battle of Washita River, an attack which was at the time labeled a "massacre of innocent Indians" by the Indian Bureau. By the time of the Little Bighorn, half of the 7th Cavalry's companies had just returned from 18 months of