First Lieutenant Delancey Floyd-Jones was in command of Company C, 4th Infantry while stationed at Ft. Steilacoom between the years 1853–54. Lt. Floyd-Jones graduated from the USMA in 1846—45th in his class—and he saw subsequent service in the U.S.-Mexican War with the 4th Infantry Regiment.
A founding member of the Aztec Club, Lt. Floyd-Jones remained with the 4th Regiment after the war. He served at several posts on the Pacific Coast until the outbreak of the Civil War.
In 1861, Capt. Floyd-Jones was promoted to the rank of Major with the 11th Infantry; he saw significant combat action with the 11th in the Eastern Theater. Commended for his command at the Wheatfield in Gettysburg, Major Floyd-Jones took a Lt. Colonelcy with the 19th Infantry in August 1863. In 1865, Lt. Col. Jones assumed command of the 19th Infantry.
After the war, Floyd-Jones commanded several outposts, forts, and the 6th and 3rd Infantry Regiments. He retired from the Army in 1879.