On April 30, 1945, Adolf Hitler put a pistol to his head and pulled the trigger. The Third Reich did not die with him. It had a successor, and that successor was not Hermann Göring or Joseph Goebbels. It was a quiet, professional naval officer named Karl Dönitz.

For twenty-three days, from April 30 to May 23, 1945, Dönitz was the leader of Nazi Germany, the president of the Reich, the Supreme Commander of the Armed Forces, the man who signed the final surrender. He was technically the last Führer. And then he lived for another thirty-five years. While other Nazi leaders were hanged at Nuremberg, while others killed themselves in bunkers, while others fled to South America, Dönitz served ten years in Spandau Prison, walked out a free man, and lived quietly in northern Germany until 1980.

He never apologized. He never admitted guilt. He died at eighty-nine, still defending his actions, still insisting he was just a sailor doing his duty. Dönitz was born on September 16, 1891, in Grünau, a suburb of Berlin.

His father was an engineer, a respectable middle-class professional who valued discipline and education. Drawn to the sea from an early age, Dönitz joined the Imperial German Navy as a cadet in 1910. When World War I erupted in 1914, he served first on cruisers, then transferred to the submarine service in 1916. That transfer defined his entire career.

By October 1918, his submarine was damaged during an attack on a British convoy in the Mediterranean. The boat surfaced, unable to dive, and Dönitz was captured, spending the remaining months of the war in a British prisoner of war camp. Germany’s defeat was devastating for men like him. The Kaiser abdicated, the empire collapsed, and the proud German Navy was surrendered to the British.

Dönitz returned to Germany in 1919, determined to rebuild his career in the tiny navy permitted by the Treaty of Versailles, which limited Germany to just 15,000 naval personnel and prohibited submarines entirely. When Hitler came to power in 1933, everything changed. The Nazis began secretly rebuilding German military power, and in 1935, Germany openly announced the creation of a new submarine fleet. Dönitz, now a captain with nearly two decades of experience, was given command of the first U-boat flotilla.

He threw himself into the work with passionate dedication. He developed new tactics, including the famous wolfpack strategy that would terrorize Allied shipping during World War II. Instead of submarines hunting alone, Dönitz organized them into coordinated groups that converged on convoys, attacking simultaneously from multiple directions. He also built a close relationship with his crews, knowing his submarine captains personally, visiting them before missions, debriefing them after patrols, mourning when they died.

His men called him Der Löwe, the lion, and their loyalty was absolute. When World War II began in September 1939, Dönitz commanded the entire German submarine force. He had only fifty-seven U-boats, far fewer than he believed necessary. He had argued for three hundred submarines before the war, but Hitler and the naval high command had ignored him.

Despite the limited numbers, Dönitz launched his U-boats against British shipping immediately, and the results were devastating. In the first months of the war, German submarines sank hundreds of thousands of tons of Allied shipping. The Battle of the Atlantic became the longest continuous campaign of World War II. At its peak in 1942, the U-boat campaign came close to winning.

Allied losses were catastrophic, and Britain faced the real possibility of starvation. But the tide turned. Allied codebreakers cracked the German naval codes. New radar technology made submarines vulnerable when they surfaced.

Long-range aircraft closed the mid-Atlantic gap, and escort carriers provided air cover for convoys. The hunters became the hunted. Of approximately 40,000 men who served in German submarines during the war, around 30,000 died, a 75 percent casualty rate. Dönitz sent thousands of young men to their deaths, knowing by 1943 that the battle was lost, but continuing to fight anyway.

After the war, he argued that every Allied ship hunting submarines was a resource not available elsewhere. Critics argued he sacrificed his men’s lives for nothing. Dönitz was not an early Nazi. He had not joined the party before Hitler came to power.

But over the course of the war, he became increasingly devoted to Hitler personally. Hitler treated him with respect, listening to his arguments about submarine warfare, and Dönitz was promoted to Grand Admiral in 1943, the highest rank in the German Navy. His speeches to his men were filled with Nazi rhetoric, and he issued orders praising Hitler and demanding absolute loyalty. By 1945, Dönitz was one of the most trusted men in Hitler’s inner circle.

By April 1945, the Third Reich was collapsing. Soviet forces were fighting through the streets of Berlin, and American and British armies were racing across western Germany. Hitler was trapped in his bunker. On April 28, Hitler learned that Heinrich Himmler, the head of the SS, had been secretly negotiating surrender with the Western Allies.

Hitler was furious and considered it the ultimate betrayal. Göring had also fallen from favor days earlier, after sending a message suggesting he should take over leadership since Hitler was trapped in Berlin. Hitler interpreted this as a coup attempt and stripped Göring of all his positions. With both Himmler and Göring disgraced, Hitler needed a new successor.

He chose Dönitz. Several factors influenced the decision. Dönitz had remained loyal when others had betrayed him. The Navy had not been involved in the July 1944 assassination attempt.

And Dönitz was far from Berlin, in northern Germany, where he could actually function as a leader. On April 30, Hitler dictated his final testament, naming Dönitz as his successor with the title of President of the Reich and Supreme Commander of the Armed Forces. That afternoon, Hitler shot himself. That evening, Dönitz received a telegram informing him that he was now the leader of Germany.

He was stunned. He had not expected this. But he accepted the responsibility, believing it was his duty. He established his headquarters in Flensburg, a small city near the Danish border, and gathered what remained of the German government around him.

Dönitz faced an impossible choice. Unconditional surrender was inevitable. His strategy was to delay surrender to the Soviets as long as possible while allowing German soldiers and civilians to flee westward into areas controlled by the Western Allies. He hoped to surrender to the Americans and British while continuing to fight the Soviets.

Over the following days, millions of Germans managed to escape Soviet occupation. But the Allies would not cooperate with a partial surrender. They insisted on unconditional surrender on all fronts simultaneously. On May 7, 1945, General Alfred Jodl signed the unconditional surrender at Allied headquarters in Reims, France.

The following day, Field Marshal Wilhelm Keitel signed a second surrender document in Berlin for the benefit of the Soviets. The war in Europe was over, but Dönitz remained in power for another two weeks. On May 23, 1945, British soldiers arrived at Flensburg and arrested Dönitz and his entire government. The Third Reich was finally over.

It had lasted twelve years under Hitler and twenty-three days under Dönitz. Now came the question of justice. Dönitz was included in the list of defendants at the Nuremberg trials. The case against him focused on his role in the U-boat campaign, particularly the Laconia Order of September 1942, which ordered all U-boats to stop rescue attempts.

The prosecution argued this was an order to commit murder. Dönitz defended himself by arguing the order merely prohibited active rescue operations, arguing that submarines were too vulnerable to stop for rescues. His defense received unexpected help from Admiral Chester Nimitz, commander of American forces in the Pacific, who testified that the US Navy had conducted unrestricted submarine warfare against Japan in exactly the same manner. If Dönitz was guilty, then so were American submarine commanders.

In the end, the Tribunal convicted Dönitz on two counts, crimes against peace and war crimes. He was acquitted on the conspiracy charge. The judges found that his submarine warfare tactics were not criminal given that both sides had used similar methods, but they found him guilty for his role in waging aggressive war. The sentence was ten years in prison, the lightest sentence given to any of the major convicted defendants.

Göring had been sentenced to death. So had Ribbentrop, Keitel, Jodl, and others. Dönitz alone among the top Nazi leadership received a prison sentence he could actually survive. Factors influencing the judges included his status as a military officer rather than a political leader, and the Nimitz testimony undermining the submarine warfare charges.

Dönitz was transferred to Spandau Prison in Berlin, where he served his sentence alongside six other convicted Nazi leaders. He adapted to prison life with the same discipline he had applied to his naval career. He followed the rules, maintained his health, read voraciously, and began writing his memoirs, carefully crafting the narrative that would define his legacy. On October 1, 1956, Dönitz walked out of Spandau a free man.

He had served his full ten-year sentence. He settled in Aumühle, a small village near Hamburg, and lived quietly, focusing on writing and defending his reputation. He published two books. The first, Ten Years and Twenty Days, appeared in 1958, defending his tactics and emphasizing the bravery of his crews.

The second, My Ever-Changing Life, was a broader autobiography published in 1968. Both books presented Dönitz as a professional soldier, a man of duty caught up in events beyond his control. He maintained this narrative for the rest of his life. He was a sailor, not a Nazi.

He had fought for Germany, not for Hitler. He never acknowledged the broader crimes of the Nazi regime. He claimed ignorance of the Holocaust. This claim was dubious.

As a Grand Admiral and member of Hitler’s inner circle, he would have had access to information about Nazi crimes. Dönitz’s personal tragedy was the loss of both sons during the war. Klaus Dönitz, the elder son, a naval officer, was killed in May 1944 when his vessel was attacked by Allied aircraft. He was twenty-four.

Peter Dönitz, the younger son, served on U-boats and was killed in May 1943 when his submarine U-954 was sunk in the North Atlantic. He was twenty-one. Both sons died within a year of each other, in the naval service their father led. Dönitz rarely spoke about them in public.

Karl Dönitz died on December 24, 1980, in Aumühle. He was eighty-nine years old. He had outlived almost everyone from the Nazi era. His funeral was controversial.

Hundreds attended, including many former naval officers and U-boat veterans, some wearing old uniforms, some giving the Nazi salute. The German government distanced itself from the event. No official representatives attended. He left behind a complex legacy.

From a military perspective, he was a skilled naval commander whose wolfpack tactics revolutionized submarine warfare. But he served a criminal regime, accepted promotion from Hitler, made speeches supporting Nazi ideology, and accepted leadership of a state built on genocide. He never acknowledged the crimes of the Nazi regime, never apologized for serving Hitler, never expressed remorse for the millions who died. He maintained until his death that he was simply a sailor doing his duty.

The last Führer of the Third Reich ended his days as a quiet pensioner in a Hamburg suburb, maintaining his version of the truth. History has not fully agreed with that version.