Marcus Albert Reno (November 15, 1834 – March 30, 1889) was a United States career military officer who served in the American Civil War and under George Armstrong Custer in the Great Sioux War against the Lakota (Sioux) and Northern Cheyenne.
Reno is most noted for his prominent role in the Battle of the Little Bighorn.
This has since been a subject of controversy regarding his command decisions in the course of one of the most infamous defeats in the history of the United States military.