John Richmond Alexander was born in Washington, Texas, on 13 September 1891, son of William R. and Julia (Sloane) Alexander. In 1911 he graduated as an honor student from Navasota (Texas) High School, and in 1915 received the degree of Bachelor of Science in mechanical engineering from the Agricultural and Mechanical College of Texas, College Station. During 1915 and 1916 he served with the Texas National Guard, entering the US Naval Reserve in the rank of Ensign on 7 June 1918. On 18 September of the same year, he was transferred to the US Navy, resigning from the naval service on 17 March 1919. He rejoined the Naval Reserve Force in the rank of Ensign on 17 July 1919 (date of rank 18 September 1919), and subsequently advanced in grade, attaining that of Captain, to date from 10 November 1945.
Upon receiving his appointment in June 1918, he had instruction until September of that year at the Naval Academy, Annapolis, Maryland. Following an assignment at the Naval Training Camp, Pelham Bay Park, New York, he attended Submarine School at New London, Connecticut, from which he graduated in March 1919. He remained there until his resignation became effective later in March 1919.
As a civilian, he was employed between 1919 and 1928 by the Texas Company, in charge of the Mechanical Department, Northern Section, (building and operating new boiler and power houses as well as stills). During the remaining period, 1921-1928, he was in charge of plant operation at the Texas Company's plants at New Orleans, Louisiana; Norfolk, Virginia; Providence, Rhode Island; and Naamans, Delaware. From 1929 to 1934 he held the position of General Superintendent of Water Terminals for the Continental Oil Company, and Vice-President of Continental Steamship Company.
He completed courses in oil chemistry and industrial engineering in 1937 and 1938, respectively, at Columbia University, New York City, New York.
He was ordered to the Chemical Warfare School at Edgewood (Maryland) Arsenal in September 1940, and graduated in the chemical warfare course in October 1940. Called to active duty in the Naval Reserve in April 1941, he was ordered to the New York Naval Shipyard, Brooklyn, New York, and served as Assistant Machinery Superintendent until September 1941. He served during September and October 1941 in the Office of the Inspector of Naval Material, Atlanta (Georgia) District, after which he was Resident Inspector of Naval Ordnance, Houston, Texas. In January 1943 he became Liaison Officer Petroleum Pool in the Third Naval District, New York, New York. Between March and May 1944, he served as Naval Troop Commander on SS GW Julian, and in June of that year, reported as Assistant Squadron Engineer Officer on the staff of Commander Seventh Fleet.
In August 1944 he joined the staff of Commander Task Group SEVENTY THREE POINT TWO, as Deputy Coordinator of Refits. He continued to serve in that capacity until April 1945, with further duty which extended to December 1945 as Commander Submarine Repair Unit #137.
He was Material and Logistics Officer on the staff of Commander Florida Group, Atlantic Reserve Fleet, January 1946 until March 1948 when he transferred in a similar capacity to the staff of Commander New York Group, Atlantic Reserve Fleet. While in that assignment, he was in command of that group between July and October 1948. In February 1952 he became Inspector of Naval Material, New York, New York, where he continued to serve until relieved of active duty on 2 February 1954.
Captain Alexander had the Naval Reserve Medal with Bronze Star; the World War I Victory Medal; the American Defense Service Medal; the American Campaign Medal; the Asiatic-Pacific Campaign Medal; the World War II Victory Medal; the Armed Forces Reserve Medal; and the National Defense Service Medal.