On the morning of 21 June 1919, the British guard ships had left for exercises at Scapa Bay, leaving only a skeleton watch over the anchorage — exactly the opening von Reuter had been waiting for. He believed the Armistice had expired that day and that the British were about to seize the fleet; in his mind, the choice was stark: act now, preserve German naval honour, and deny the Allies the ships, or watch them be taken as trophies. At 10:30am, he gave the signal. Passed ship to ship by a pre-arranged code, the order moved through the fleet with astonishing speed and discipline. Across the anchorage, German sailors sprang into action, opening sea-cocks, smashing pipes, and setting valves to flood the hulls from within. What followed was chaos on a colossal scale: great ships began to list alarmingly, some capsizing almost at once, others taking minutes, then hours, to settle by the stern and disappear beneath the surface. The harbour filled with the groaning of tortured metal, the thunder of moving water, the hiss of steam, and the desperate cries of men scrambling for rafts and boats. British guard ships raced back as soon as they saw what was happening, but the scene was already spiralling beyond control. In the confusion, some British sailors fired on German crews trying to abandon ship — and nine German men were killed, the last casualties of the First World War. By the end of the day, 52 of the 74 vessels had gone to the bottom, some 400,000 tons of warships in all, including battleships such as SMS Friedrich der Grosse and SMS Bayern — the single greatest loss of warships in a single day in history. Admiral Madden was furious: the ships had been earmarked for distribution among the Allied powers as war reparations, and now the prize had vanished before their eyes. Von Reuter was arrested and taken prisoner, yet in Germany he was celebrated as a hero who had saved the navy's honour. In an irony fit for history, the scuttling also simplified the peace negotiations at Versailles, because there were suddenly far fewer ships left to divide. The Treaty of Versailles was signed on 28 June 1919 — exactly one week later.