Marcellus Chiles was born on 5 February 1895 in Eureka Springs, Arkansas, to attorney John Horne Chiles and Lillian Irene Hughes. He later moved to Denver, Colorado, where his father worked as a lawyer. He was a student at Colorado College in Colorado Springs, where he was a member of the football team, when the First World War began. After attending an officers’ training camp, he was appointed a second lieutenant in the US Army in August 1917. On 18 February 1918 Marcellus Chiles was promoted to first lieutenant.
First Lieutenant Marcellus Chiles was sent to Europe with the 356th Infantry Regiment, 89th Division where he first saw action at the SAINT MIHIEL Salient in northeast France in August 1918. On 3 November 1918, four days after being promoted to captain, Captain Marcellus H Chiles participated in an advance near Le Champy Bas as part of the Meuse-Argonne Offensive. After all of the senior officers of his battalion had been wounded or killed, Captain Chiles found himself in command of his battalion. His company had been halted by intense machine gun fire when he assumed command of the battalion. Realising the necessity of getting the advancing moving forward once more, he picked up a rifle and began to advance all the while encouraging his men to follow. Leading his men through a waist-deep stream he was shot in the stomach by a German sniper and, although badly wounded, Captain Chiles refused to be evacuated for treatment but continued to crawl after his troops after reaching the stream’s far bank. After turning over command of the battalion, he was evacuated to a hospital, where he died on 5 November 1918.
For his actions on 3 November 1918 Captain Marcellus H Chiles was posthumously awarded the Distinguished Service Cross. Following a review by the military authorities this award was upgraded to the Medal of Honor on 15 April 1919. His citation reads:1
"When his battalion, of which he had just taken command, was halted by machinegun fire from the front and left flank, he picked up the rifle of a dead soldier and, calling on his men to follow led the advance across a stream, waist deep, in the face of the machinegun fire. Upon reaching the opposite bank this gallant officer was seriously wounded in the abdomen by a sniper, but before permitting himself to be evacuated he made complete arrangements for turning over his command to the next senior officer, and under the inspiration of his fearless leadership his battalion reached its objective. Capt. Chiles died shortly after reaching the hospital."
Captain Marcellus Chiles is buried in the Meuse-Argonne American Cemetery and Memorial, Plot C, Row 31, Grave 23.