Siege of Belfort
1870 CE.
Shown on the map at 47.638°, 6.863°.
The siege of Belfort (3 November 1870 – 18 February 1871) was a 103-day military assault and blockade of the city of Belfort, France by Prussian forces during the Franco-Prussian War. The French garrison held out until the January 1871 armistice between France and the German Empire obligated French forces to abandon the stronghold in February 1871. Belfort is located in a gap between the mountainous southern Vosges and the Jura Massif, strategically positioned as the gateway between Alsace and central France. At the beginning of the war, the French Army of the Rhine was routed in northern Alsace. The fall of Strasbourg on 28 September 1870 allowed the German army under August von Werder to move south against Belfort. Upon hearing of the approaching German army, Pierre Philippe Denfert-Rochereau, commander of Belfort, began constructing fortifications around the city, expanding those originally built by Vauban. Werder's forces reached Belfort and invested the city on 3 November. The intransigent resistance by the French forces stopped the Germans from completing an effective encirclement of the city. General Charles Denis Bourbaki assembled an army intending to relieve Belfort.
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