Dwight Merle Agnew was born in Fredericktown, Ohio, on 1 January 1902, son of Murray J. and Emma Louise (Follin) Agnew. He attended Fredericktown High School and Denison University, Granville, Ohio, for one year, prior to entering the US Naval Academy, Annapolis, Maryland, on appointment from his native state in 1922. Graduated and commissioned Ensign on 3 June 1926, he progressed in rank, attaining that of Captain, to date from 1 August 1942. On 1 July 1956 he was transferred to the Retired List of the US Navy and was advanced to, the rank of Rear Admiral on the basis of combat awards.
Following graduation from the Naval Academy in 1926, he joined USS Omaha for communication duty and between May and November 1927 had detached duty at the Naval Radio Station, San Francisco, California. Detached from the Omaha in April 1930, he continued service afloat in USS Gamble, a fast mine layer stationed at Pearl Harbor, TH, until May 1933, when he was assigned to the Division of Naval Communications, Office of the Chief of Naval Operations, Navy Department, Washington, DC. In June 1935 he reported on board USS Nevada and during his last year in that battleship, his Turret Number 4 won the Majorie Sterret and Admiral Trenchard prizes for Excellence in Gunnery.
From June 1939 until October 1941 he was assigned as Communications Officer at the US Naval Station, Guantanamo Bay, Cuba. He next had instruction at the Naval Mine Warfare School, Yorktown, Virginia, prior to assuming command, in October 1941, of the fast mine sweeper Trever. The Trever was based at Pearl Harbor, TH, when the Japanese attacked the Naval Base there in 7 December 1941 and subsequently participated in engagements at Guadalcanal and Tulagi. "For extraordinary heroism...during operations in the Solomon Islands Area in August and October 1942..." he was awarded the Navy Cross. The citation further states in part:
"Participating in the initial attack on Guadalcanal, August 7 to 9, 1942, as well as on numerous other occasions, Commander Agnew's ship acted as a screen for the transports, landing supplies and reinforcements, and, during attack, as a fire support minesweeper. From October 23 to 25, Commander Agnew, as Commander of a Task Unit, again entered the Solomon Islands waters, carrying vitally needed material which was successfully unloaded at Tulagi. When retiring, his Unit was attacked by a force of three Japanese destroyers and during the ensuing battle he fought his ships with such brilliant success that none received serious damage and there was only small loss of personnel, while his vessels inflicted several hits on one enemy destroyer, setting it afire..."
He was also entitled to the Ribbon for, and a facsimile of the Navy Unit Commendation awarded USS Trever for outstanding services in the Solomon Islands area.
Detached from command of the Trever in March 1943, he was ordered to the Bethlehem Steel Company, San Francisco, California, to fit out and put into commission the new 2200 ton destroyer Heermann. He assumed command of that destroyer upon her commissioning, 6 July 1943, and commanded her during the assault and occupation of Kwajalein, Majuro Eniwetok, Tarawa, Emirau and Green Island. He was awarded the Bronze Star Medal, with Combat "V" and was cited as follows:
"For meritorious achievement during operations against enemy Japanese forces in the Pacific War Area from October 1943 to April 1944. During the first part of this period when the HEERMANN participated in the Gilbert Islands operation, (he) directed the sinking of a small enemy surface craft inside Tarawa Lagoon on November 20 and, following this action, furnished close fire support for two days. Patrolling, screening and supporting the Kwajalein-Majuro operation, he rendered invaluable assistance in the occupation of Eniwetok Atoll and later operated in support of the Emirau Occupation on the Truk-Kavieng supply line, thereby contributing materially to our success in these strategic areas..."
In May 1944 he joined the staff of Commander Amphibious Forces, Pacific as Assistant Operations Officer and in that capacity saw action during the assault on and capture of Saipan, Tinian and Guam. He was entitled to the Ribbon for, and a facsimile of the Navy Unit Commendation awarded USS Rocky Mount, which was flagship of Commander Amphibious Forces, Pacific. He assumed command of USS Harry Lee in February 1945 and commanded her during the assault on and capture of Iwo Jima. He continued to command that assault transport, participating in "Magic Carpet" operations (returning veterans from the War zone), until she was decommissioned at New York in 1946. From July of that year until June 1947 he had instruction (Senior Course) at the Naval War College, Newport, Rhode Island, after which he was Assistant Chief of Naval Communications for Plans and Liaison, Office of the Chief of Naval Operations, Navy Department, Washington, DC.
In November 1949 he reported as Navy Member on the Joint Planning Staff, Joint American Military Mission for Aid to Turkey, with headquarters in Ankara. He was Commander Destroyer Squadron TEN, of the Atlantic Fleet, during the period January 1952 to February 1953, then was assigned to the National Security Agency, Washington, DC. On 1 July 1956 he was transferred to the Retired List of the US Navy.
In addition to the Navy Cross, the Bronze Star Medal with Combat "V," and the Navy Unit Commendation Ribbon with star, Rear Admiral Agnew had the American Defense Service Medal; American Campaign Medal; Asiatic-Pacific Campaign Medal with one silver star and three bronze stars (eight operations); World War II Victory Medal; China Service Medal; and the National Defense Service Medal.