The army of Marshal McMahon bottled up in the French fortress city of Metz surrendered en mass to the beseiging Prussians. Over 140,000 French soldiers marched into captivity, marking the effective end of the Franco-Prussian War.
The Franco-Prussian War of 1870-71 is often little known outside the field of military history and I sometimes feel it failed to capture the imagination of later generations (outside France and Germany) in the way that the Crimean and American Civil wars did. However, the impact of the war in Europe was profound and long-lasting. Not only did it mark the creation of a unified Germany, but it also (through the German annexation of Alsace and Lorraine) helped lay the groundwork for the far more destructive war that broke out in August 1914.