Original Scarce Portrait of Karl Dönitz. Großadmiral Karl Dönitz (16.09.1891 † 24.12.1980) was a German admiral during the Nazi era who briefly succeeded Adolf Hitler as the German head of state in 1945. As Supreme Commander of the Navy since 1943, he played a major role in the naval history of World War II. He was convicted of war crimes at the Nuremberg trials in 1946. Condition as seen. A5 size.