Winfield Scott Edgerly 27, 1875. From May to September 1876, the 7th Cavalry, including Edgerly, participated in the Sioux Expedition. Edgerly was promoted to first lieutenant in the 7th Cavalry effective June 25, 1876. The regiment was engaged in the Battle of the Little Bighorn on June 26–27, 1876. Edgerly was the second in command of Company D, serving under Captain Thomas Weir; Company D was assigned to Captain Frederick Benteen's Battalion. Prior to the battle, Lieutenant Colonel George Armstrong Custer was discussing upcoming events with his junior officers; Edgerly expressed enthusiasm about the possibility of success; Custer replied that success depended on
George Armstrong Custer A roommate noted, "It was alright with George Custer, whether he knew his lesson or not; he simply did not allow it to trouble him." Under ordinary national conditions, Custer's low class rank would result in an obscure posting, but Custer had the "fortune" to graduate as the Civil War broke out. All officers were needed. Like the other graduates, Custer was commissioned as a second lieutenant; he was assigned to the 2nd U.S. Cavalry Regiment and tasked with drilling volunteers in Washington, D.C. On July 21, 1861, he was with his regiment at the First Battle of Bull Run