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.
George Armstrong Custer and form a skirmish line. They were soon overcome by mounted Lakota and Cheyenne warriors who counterattacked "en masse" against Reno's exposed left flank, forcing Reno and his men to take cover in the trees along the river. Eventually, however, this position became untenable, and the troopers were forced into a bloody retreat up onto the bluffs above the river, where they made their own stand. This, the opening action of the battle, cost Reno a quarter of his command. Custer may have seen Reno stop and form a skirmish line as Custer led his command to the northern end