John P . Cromwell Captain John Philip Cromwell ( September 11 , 1901 – November 19 , 1943 ) was the most senior submariner awarded the Medal of Honor in World War II and one of the three submarine officers who received it posthumously . In some ways similar to his fellow honoree , Howard Gilmore , Cromwell consciously chose to sacrifice his own life to safeguard the lives of others in combat that took place in November 1943 . Early Life and Career . Cromwell was born in Henry , Illinois , on September 11 , 1901 . Appointed to the U . S . Naval Academy in 1920 , he graduated in June 1924 and served initially in the battleship USS " Maryland " school and was assigned to during 1927 – 29 . He next had three year ' s diesel engineering instruction , followed by further tours of duty in submarines . Lieutenant Cromwell commanded in 1936 – 37 , then served on the staff of Commander Submarine Division 4 . He was promoted to the rank of Lieutenant Commander in 1939 and spent two years in Washington , D . C . with the Bureau of Engineering and Bureau of Ships . In May 1941 , he became Engineer Officer for the Pacific Fleet submarine force . World War II . During 1942 – 43 , Cromwell commanded Submarine Divisions 203 , 44 and 43 , flying his pennant in . Following promotion to Captain , he went to sea in as prospective commander of a mid - Pacific submarine wolf pack . was commanded by LCDR Fred Connaway , making his first war patrol . If conditions warranted , Cromwell would form a wolfpack with and either or under his direction . As a senior officer , Cromwell was completely familiar with the plans for the upcoming Battle of Tarawa , Operation Galvanic , and knew a lot more about ULTRA - and its source - than anyone else on . It was Cromwell ' s first war patrol also . While attacking a Japan ese convoy on November 19 , 1943 , " Sculpin " was forced to the surface , fatally damaged in a gun battle and abandoned by her surviving crew members . Captain Cromwell , who knew secret details of the impending operation to capture the Gilbert Islands , deliberately remained on board as she sank . For his sacrificial heroism in preventing the enemy from obtaining this information , he posthumously received the Medal of Honor . Medal of Honor Action . After a brief overhaul , left Pearl Harbor for her ninth war patrol on 5 November 1943 . After refueling at Johnston Island on 7 November , she departed for her assigned station northeast of Truk . On 29 November , COMSUBPAC radioed to order CAPT Cromwell to activate the wolfpack . When failed to acknowledge the message , even after several repetitions , she was assumed - correctly - to have been lost at sea . It wasn ' t until after the war that the details of her loss - and that of John Cromwell - to enemy action became known from both Japanese sources and surviving crewmembers who had been prisoners of war . Around noon , Connaway attempted to bring back to periscope depth , seeking another opportunity to attack . However , while coming up , the broken depth gauge stuck at 125 feet , confusing the diving officer , and causing the boat to broach the surface in full view of " Yamagumo " , which was still patrolling the area . As crash - dived again , the Japanese destroyer dropped a string of 18 depth charges , severely damaging the boat and causing temporary loss of depth control . Numerous leaks developed in the hull , and so much water came on board that the submarine was forced to run at high speed to maintain depth . This invited a second Japanese attack that did even more damage . At this point , Connaway concluded that the only chance of saving his crew was to come to the surface and fight it out there . surfaced , and with decks awash , her crew manned the deck guns . The result of this uneven contest was hardly in doubt . " Yamagumo ' s " first salvo hit ' s conning tower , killing the entire bridge watch team , including Connaway and his executive and gunnery officers . The gun crew died almost instantly from shrapnel . The senior ship ' s officer surviving , a reserve lieutenant , ordered the boat scuttled and the crew to abandon ship . This action left CAPT Cromwell facing a fateful choice . With his personal knowledge of both ULTRA and GALVANIC , he realized immediately that to abandon ship and become a prisoner of the Japanese would create a serious danger of compromising these vital secrets to the enemy under the influence of drugs or torture . For this reason , he refused to leave the stricken submarine and gave his life to avoid capture . He and 11 others rode on her final plunge to the bottom , where her secrets would be safe forever . After Action Summary . 42 members of " Sculpin ' s " crew - three officers and 39 enlisted men - were pulled from the sea by the Japanese , though one of the latter , badly wounded , was thrown back . The 41 survivors were taken to Truk and interrogated for ten days by Japanese intelligence officers . The group was divided in half for transport back to Japan on two escort carriers - 21 on IJS " Chuyo " and 20 on IJS " Unyo " . Those on " Unyo " arrived in Japan in early December and spent the rest of the war working in the Ashio copper mines , after which they were repatriated to tell their story . On the evening of 3 December 1943 , 240 miles southeast of Yokosuka - with some help from ULTRA - sank " Chuyo " , and only one of the prisoners onboard survived . When the story of John Cromwell ' s heroic sacrifice was revealed in the accounts of the survivors , COMSUBPAC VADM Charles Lockwood nominated him for the Medal of Honor . The award was approved and presented posthumously to Cromwell ' s widow after the war . Medal of Honor . Rank and organization : Captain , U . S . Navy . Born : 11 September 1901 , Henry , Ill . Appointed from : Illinois . Other Navy award : Legion of Merit . Citation For conspicuous gallantry and intrepidity at the risk of his life above and beyond the call of duty as Commander of a Submarine Coordinated Attack Group with Flag in the U . S . S . " Sculpin " , during the Ninth War Patrol of that vessel in enemy - controlled waters off Truk Island , November 19 , 1943 . Undertaking this patrol prior to the launching of our first large - scale offensive in the Pacific , Captain Cromwell , alone of the entire Task Group , possessed secret intelligence information of our submarine strategy and tactics , scheduled Fleet movements and specific attack plans . Constantly vigilant and precise in carrying out his secret orders , he moved his underseas flotilla inexorably forward despite savage opposition and established a line of submarines to southeastward of the main Japanese stronghold at Truk . Cool and undaunted as the submarine , rocked and battered by Japanese depth - charge s , sustained terrific battle damage and sank to an excessive depth , he authorized the " Sculpin " to surface and engage the enemy in a gun - fight , thereby providing an opportunity for the crew to abandon ship . Determined to sacrifice himself rather than risk capture and subsequent danger of revealing plans under Japanese torture or use of drugs , he stoically remained aboard the mortally wounded vessel as she plunged to her death . Preserving the security of his mission at the cost of his own life , he had served his country as he had served the Navy , with deep integrity and an uncompromising devotion to duty . His great moral courage in the face of certain death adds new luster to the traditions of the United States Naval Service . He gallantly gave his life for his country . Other Honors . In 1954 , the destroyer escort was named in his honor . The Navy ' s Submarine Learning Center at the submarine base in Groton Ct was also named for him , Cromwell Hall .