Karl-Friedrich Merten

https://en.wikipedia.org/wiki/Karl-Friedrich_Merten

Karl-Friedrich Merten (15 August 1905 – 2 May 1993) commanded the U-boat U-68 in Nazi Germany's Kriegsmarine during World War II. He received the Knight's Cross of the Iron Cross with Oak Leaves. Merten was credited with the sinking of 27 ships for a total of 170,151 gross register tons (GRT) of Allied shipping. Merten joined the Reichsmarine (navy of the Weimar Republic) in 1926. He served on the light cruisers Karlsruhe and Leipzig during the Spanish Civil War patrols.