On June 28, 1914, Kaiser Wilhelm II was preparing to indulge in a favorite pastime: racing his yacht Meteor at a regatta that is still held each year in this seafaring stronghold. When he learned of the assassination in Sarajevo of Archduke Franz Ferdinand, the heir to the Hapsburg Empire, he hastened to Berlin. But he quickly returned to this Baltic Sea port, on which he lavished so much money and time in his frantic race to match or outdo British naval superiority.

In many ways, Kiel epitomized Germany’s rapid industrialization and militarization from 1870 to 1914, under Otto von Bismarck and then the kaiser. Numbers alone tell a story: In 1870, as Bismarck unified Germany, Kiel had around 30,000 inhabitants. By 1914, when Europe’s leaders stumbled into World War I, its population exceeded 227,000.

Four years later, Kiel bore witness to the depths of German defeat. A sailors’ rebellion that started here spread nationwide and helped force the abdication of the kaiser in November 1918. The next year, rather than let the Imperial Fleet fall to the enemy, German commanders on Scapa Flow, off Scotland, scuttled 52 of the fleet’s 74 vessels. Under the Treaty of Versailles, signed five years to the day after the archduke’s assassination, the proud navy was limited to just a few ships and 15,000 men — far fewer than the 35,000 German sailors who had perished in World War I.