U-905 was a Type VIIC U-boat, the workhorse design of Hitler's Kriegsmarine and the most-produced submarine class in history. She was ordered on 6 August 1942 and laid down on 26 January 1943 at H. C. Stülcken Sohn in Hamburg as yard number 802. She was launched on 20 November 1943 and commissioned under the command of Oberleutnant zur See Heinz-Ehler Brüllau on 8 March 1944. By that point in the war, the Battle of the Atlantic had effectively been lost by the Germans; Allied convoy escorts and aircraft were sinking U-boats faster than the Kriegsmarine could replace them, and the Type VIIC's relatively shallow operating depth and limited submerged endurance left her badly outclassed by Allied detection and weapon technology.

The boat was a standard Type VIIC: 67.1 metres long, 6.2 metres in the beam, displacing 769 tons on the surface and 871 submerged. Two Germaniawerft F46 supercharged diesels drove her on the surface at up to 17.7 knots; two Siemens-Schuckert electric motors gave her a maximum of 7.6 knots submerged. She could dive to 230 metres, carried five torpedo tubes (four bow, one stern), fourteen torpedoes or twenty-six mines, plus an 8.8 cm deck gun and anti-aircraft armament. The complement was between 44 and 52 men. None of this saved her, and by 1945 nothing was saving the Type VIICs in any number. Of the more than 700 boats of this class commissioned, around 80 percent were lost.

On 27 March 1945 - with the Soviet army on the outskirts of Berlin and the Allies crossing the Rhine - U-905 was sunk by depth charges in the North Minch by a British frigate. Bernhard Schwarting, who had taken command of the boat from her original captain, and forty-four other crewmen were lost. No survivors. The Minch in late March is cold and rough; even men who escaped the hull would not have lasted long. The boat sank to the floor of the strait and stayed there. Six weeks later, on 8 May 1945, Germany surrendered. Had U-905 survived another month and a half, her crew would have come home.

The submariners of the Kriegsmarine had the worst casualty rate of any service in the Second World War: roughly 75 percent of all U-boat crewmen died at sea. The men of U-905 were among them - young Germans in a war they did not start and probably did not end up believing in, ordered to take an obsolete weapon into a battle that was already lost, sunk in a cold strait at the edge of Europe by a frigate doing its job. They were not heroes of the Third Reich; they were sailors, most of them in their early twenties, with families in Hamburg and Bremen and Kiel who would learn in the chaos of the war's last weeks that they had been killed. The Minch keeps their bones now. The wreck has been located, though the exact coordinates are not always published; the boat lies undisturbed in deep cold water, a maritime grave that will likely never be opened.