Thomas Custer in the Yellowstone Expedition of 1873, where he fought in the Battle of Honsinger Bluff, and the Black Hills Expedition of 1874. Custer was appointed captain in 1875 and given command of Company C of the 7th Cavalry. In 1874, at the trading post at Standing Rock Agency, Custer participated in the arrest of chief Rain-in-the-Face (Lakota), suspected in the 1873 murder of Dr. John Honsinger. During the 1876 Little Bighorn campaign of the Black Hills War, he served as aide-de-camp to his older brother Lt. Col. George A. Custer and died with his brother on June 25, 1876. Lt.
Battle of the Little Bighorn unusually large numbers of Native Americans, Crook held the field at the end of the battle but felt compelled by his losses to pull back, regroup, and wait for reinforcements. Unaware of Crook's battle, Gibbon and Terry proceeded, joining forces in early June near the mouth of Rosebud Creek. They reviewed Terry's plan calling for Custer's regiment to proceed south along the Rosebud while Terry and Gibbon's united forces would move in a westerly direction toward the Bighorn and Little Bighorn rivers. As this was the likely location of native encampments, all army elements had been instructed to converge there