Karl Donitz was born on September 16, 1891 in Berlin, Germany. His father, Emil, was an engineer and he had one sibling, an older brother named Friedrich. On April 4, 1910, he joined the German Navy with the rank of sea cadet. By April 15th, he was already promoted to the rank of midshipman.

On September 27, 1913, Donitz was promoted to the rank of sub lieutenant. At the beginning of World War 1, he was stationed on the SMS Breslau, a light cruiser, in the Mediterranean Sea. In October of 1916, he was transferred to work on a submarine, the UC 68.

On October 4, 1918, Donitz was captured by British forces and sent to POW camp. He was released after the war in July of 1919 and found his way back to Germany. There, he rejoined the German Navy and was promoted to the rank of Lieutenant on January 10, 1921. Towards the end of the 1920s, he was commanding a torpedo boat and he was promoted to the rank of Lieutenant Commander on November 1, 1928.

On September 1, 1933, he was promoted to the rank of Full Commander and soon after was placed in command of the Emden, a cruiser that took low ranking cadets on cruises as part of their training. On September 1, 1935, Donitz was promoted to the rank of Captain and given command of a flotilla of U-Boats: U7, U8, and U9.

Prior to World War 2, Donitz began pressing his superiors for the manufacture of more submarines for the German Navy. In the event of a war, he suggested that the submarines be used to sink merchant ships and oil tankers, effectively starving Great Britain of supplies. He was also the primary advocate of grouping submarines together to form "wolf packs".

By the start of the war in 1939, Donitz was promoted to the rank of Commodore and placed in charge of all the submarines in the German Navy. Donitz was caught off guard since the German Military had been planning for the war to start in 1945. Although he only had 57 U-Boats, he did what he could and had successes in attacking British merchant ships.

On October 1, 1939, Donitz was promoted to the rank of Rear Admiral. On September 1, 1940, he was promoted again, this time to the rank of Vice Admiral. In 1941, Donitz's fleet of submarines was bolstered with a new type of U-Boat, the Type VII. When Hitler declared war on the United States on December 11, 1941, Donitz sent nine of his U-Boats to attack merchant ships on the east side of the United States in Operation Paukenschlag.

By late 1941, Donitz was becoming concerned with the increasing frequency of Allied attacks on his U-Boats. He decided that something was happening that allowed Allies to intercept communications. On February 1, 1942, he replaced the cryptographic machines on the U-Boats with a new revision of the Enigma, the M4, and it seemed to solve the problem.

In late 1942, Donitz's fleet had enough submarines to allow for his wolf pack strategy. The packs of U-Boats were able to really tear into Allied merchant ships and the British began to wonder if their fuel supply would dwindle to the point where they couldn't fight anymore. Donitz was pleased with the improvement of the Navy, but also concerned by the involvement of the American Navy.

In 1943, as the naval battle in the Atlantic started to turn sour for the Germans, Donitz continued encouraging the production of more U-Boats. By the end of the war, the German submarines were the most advanced in the world, largely thanks to his focus. On January 30, 1943, Donitz replaced his former superior, Raeder, as the Commander in Chief of the German Navy. He convinced Hitler to keep the few surface ships left in the Navy, but they continued to face heavy losses.

While Hitler was in his bunker in 1945, he chose Donitz to take over his position as head of Germany. The move was a great surprise, but Donitz readily accepted the position of President of Germany. As the Allies advanced on Germany, Donitz was forced to retreat to the city of Flensburg, the final holdout of the German government. On May 7, 1945, he ordered the surrender of all German Military Forces. On May 23, 1945, he was captured by Allied forces and made a prisoner of war.

Following the war, Donitz was charged with conspiracy to commit crimes against peace, planning and waging wars of aggression, and crimes against the laws of war. One of the reasons he was charged was that the U-Boats did not try to save passengers of ships that were sunk by them. He also allowed U-Boats to attack any targets, merchant or passenger.

He was found not guilty of 1 charge, but guilty of the latter two. The judges sentenced him to serve eleven and a half years in prison. He was sent to West Berlin's Spandau Prison, where he served a total of ten years before his release on October 1, 1956. Following his release, he moved to the city of Aumuhle and worked on writing. His first book was "Zehn Jahre, Zwanzig Tage", a collection of his memoirs from being commander of Germany's U-Boats. His second book was "Mein wechselvolles Leben", which focused on his life prior to World War 2. Karl Donitz died from a heart attack on December 24, 1980.

"I was of the opinion that the endurance, the power to endure of the people, could be better preserved if there were no Jewish elements in the nation." - Karl Donitz