Karl Dönitz was a Grand Admiral in the German Navy during WW2, the most capable leader in all of Nazi Germany. He was the architect of U-boat warfare that brought England to its knees with just 28 subs. If Hitler had listened to him, Germany would most likely have won the war. All American post war subs used his designs including our nuclear subs. After Hitler killed himself, he took over as the leader of Germany and formed the Flensburg government until he was arrested on May 23, 1945.