From Wikipedia: “This 4 May surrender would become effective at 8:00 am on 5 May; so Dönitz ordered all ships involved in Operation Hannibal to undertake a covert final evacuation voyage, while also unilaterally ordering all U-boat actions to cease. One crew in the evacuation fleet refused to set sail; so Dönitz ordered the ringleaders to be arrested for mutiny, tried by summary court martial, and shot.”
What’s the story behind those German mutineers?
Some background: Operation Hannibal was a German naval operation to evacuate German troops and civilians from East Prussia as the Red Army advanced west. This operation began on January 21, 1945, when Donitz (who was Grand Admiral at the time - Hitler was still alive) gave the order to evacuate refugees from the Baltic coast. Over the course of the next five months, up to 900,000 civilians and 350,000 soldiers were evacuated.
Throughout this operation, ships would typically: depart from German-controlled Danish ports; sail to German-controlled Baltic ports; pick up refugees and German soldiers; then sail back to Denmark. Despite the large number of people evacuated, these missions were not without peril. Russian submarines patrolled these waters and scored numerous kills during the span of the operation, the most notable one being their sinking of the Wilhelm Gustloff, which resulted in the deaths of over 9,300 persons, including more than 5,000 children.
Ten days before committing suicide, Hitler named Donitz as his successor as president of the Reich. Once Hitler committed suicide, Donitz opened negotiations with the Western Allies for a surrender and on May 4, 1945, German forces in Holland, Denmark and northwest Germany surrendered to the Western Allies. However, Germany had not yet surrendered to Russia and was continuing Operation Hannibal and the evacuation of German civilians and soldiers.
The Wikipedia article you cited did not specify a particular incident - there were, by some estimates, more than twenty-five cases where German sailors refused to set sail. But it was most likely referring to the case of German minesweeper M 612. This vessel was actually in the port of Kiel on May 3rd when the city was surrendered to the English. However, the ship left port at the discretion of her captain, Lieutenant Commander Dietrich Kropp, who intended to evacuate troops from the Baltic states.
M 612 sailed to Frederica, another Danish port, to refuel. By the time it left Frederica on May 5th, the sailors on board had heard of the surrender to the Western Allies. Under the leadership of machinist Heinrich Glasmacher, a number of soldiers mutinied, gaining access to the armory and using the pistols and rifles they obtained to subdue the officer's on board. They mutineers planned on sailing to Flensburg (a German port near the Denmark border), but en route they passed by German gunboats that noticed erratic sailing from M 612. They quickly realized that there were no officers on deck. With backup, they boarded M 612 and took the mutineers into custody. The officers on M 612 had been detained by the mutineers for two and a half hours.
There was a hasty trial. In total, twenty mutineers were put on trial, defended by a legally inexperienced NCO. Of those twenty, eleven were sentenced to death by firing squad; four were sentenced to three years in prison; five were acquitted. For those sentenced to death, they were arranged on the deck of the M 612. The entire crew of the M 612 - including those found guilty but not sentenced to death - had to attend the execution. Once shot, the bodies were weighted down and thrown overboard. The 11 mutineers put to death were:
Regarding the case of M 612, I've not seen any claim that Donitz personally learned of this mutiny and authorized the trial and execution. But as I said earlier, this wasn't the only instance of sailors refusing to set sail after the surrender to the West.
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