[4] In June 1863 he was commissioned a second lieutenant in the newly formed 7th Indiana Volunteer Cavalry Regiment[5] and served as a recruiting officer.
Indiana war governor Oliver P. Morton assisted in an appointment to major in the 7th U.S. Cavalry and George Armstrong Custer recommended his promotion.
[7] On November 27, 1868, as second in command at the Battle of Washita River, Elliott broke off from the main body to chase fleeing Indians.
[8] Being under threat of losing his tactical advantage and fighting a far larger force of approaching Indians, George Custer left the area without knowing the fate of his subordinate and troops.
Elliot and his men were found by Custer that December when he, accompanied by General Sheridan, led a force 1,700 strong back to the Washita.