Background
He was born in Hamburg, Germany and began his naval career in April 1931 as a Seekadett.
He was born in Hamburg, Germany and began his naval career in April 1931 as a Seekadett.
He first served on the light cruiser Nürnberg for more than two years, including nine patrols in the first year of the war. In March 1941 Jahn joined the U-boat force and his first patrol were on board U-98 in September 1941. Later in November he commissioned U-596.
On his second patrol he broke through the Strait of Gibraltar and went on to become one of the most successful U-boat commanders in the Mediterranean Sea.
In July 1943 he left the boat and became the commander of the 29th U-boat Flotilla. In September 1944 he fell into French captivity, where he spent nearly two years.
Ships attacked Bibliography.