Hans - Rudolf Rösing Hans - Rudolf Rösing ( 28 September 1905 – 16 December 2004 ) was a German U - boat commander in World War II and later served in the Bundesmarine . He was also a recipient of the Knight ' s Cross of the Iron Cross ( ) . The Knight ' s Cross of the Iron Cross was awarded to recognise extreme battlefield bravery or successful military leadership . Military career . Rösing joined the Reichsmarine in April 1924 as a Seekadett , gaining his commission as Leutnant zur See in October 1928 , and surviving on the light cruisers and . Germany was forbidden to operate submarines under the Treaty of Versailles ; and in the early 1930s " Oberleutnant zur See " Rösing was one of a small number of chosen personnel who were detached to foreign navies to gain experience in submarines . After spending two years at the " Unterseebootsabwehrschule " , Rösing , recently promoted " Kapitänleutnant " , was given his first submarine command when he commissioned the new . After two years in this small Type IIB coastal submarine , he took command of , a larger Type VIIA ocean - going boat . In 1937 Rösing was given command of another Type IIB , , and assigned to the " Torpedoerprobungskommando " , responsible for the testing of new torpedo types . After a year in this post he was appointed commander of 5th U - boat Flotilla - Flotille Emsmann - at Kiel . July 1939 saw Rösing promoted to " Korvettenkapitän " . Following a short spell of duty on the staff of the " Befehlshaber der U - Boote " ( Dönitz , q . v . ) , Rösing was posted to command 7th U - boat Flotilla at Kiel . This command lasted until 21 May 1940 , at which time he took over the Type VIIB boat from her highly successful previous commander , Herbert Schultze . In the course of his two war patrols with " U - 48 " , Rösing showed himself to be as capable a commander as he was a staff officer , sinking 12 ships totaling over 60 , 000 tons , and earning himself the U - Boat War Badge , Iron Cross First Class and Knight ' s Cross of the Iron Cross . Rösing left " U - 48 " in December 1940 , and was appointed liaison officer to the Italian submarine force operating out of Bordeaux in occupied France . After some months he was given command of 3rd U - boat Flotilla , but in August 1941 returned to the staff of the Befehlshaber der U - boote . In July 1942 , Rösing was appointed as FdU West ( " Führer der U - boote West " ) , with headquarters in both Paris and Angers ; he was responsible for all boats committed to the Battle of the Atlantic , and thus a great majority of the entire U - boat fleet . In February 1943 he was promoted to " Fregattenkapitän " , and one month later to " Kapitän zur See " . He remained as FdU West until autumn 1944 , when the Allied liberation of France forced the Kriegsmarine to transfer the remaining boats of 2nd and 7th U - boat flotillas to bases in Norway , Denmark , and northern Germany . After the German surrender in May 1945 , Rösing spent about a year in British captivity before being released . Serving as a member of the Naval Historical Team he subsequently joined the post - war Navy , and was given command of German naval units operating in the North Sea ( Marine - Abschnittskommando Nordsee ) , and later Military District I , rising to the rank of Konteradmiral . He retired from active service in 1965 , having added to the Bundesverdienstkreuz ( Federal Service Cross ) to his wartime decorations . He died on 16 December 2004 , at the age of 99 .