The Siege of Paris lasting from September 19 1870 – January 28 1871 was the final defeat of the French Army during the Franco-Prussian War.

After crushing the French at the Battle of Sedan the Prussian Army lead by Wilhelm I and Helmuth von Moltke marched on to Paris and were able to lay siege to the city on September 19 1870. Governor of Paris and commander-in-chief of the city's defenses General Louis Jules Trochu made no initial effort to prevent the Prussians from besieging the city, but once the siege began the French gave a strong defense launching several sorties against the Prussian lines but were unable to break through. Upon hearing of the French surrender at Metz, French moral in Paris began to sink.

As winter approached, tensions began to arise in the Prussian high command. Field-Marshal Helmuth von Moltke was primarily concerned with a methodical siege that would destroy the detached forts around the city and slowly strangle the defending forces with a minimum of German casualties. Moltke was also worried that insufficient winter supplies were reaching the German armies investing the city, as diseases such as tuberculosis were breaking out amongst the besieging soldiers. In addition, the siege operations competed with the demands of the ongoing Loire Campaign against the remaining French field armies.

However, Prussian Prime Minister Otto von Bismarck was becoming concerned that a prolonged war was placing too much strain on the German economy, and that an extended siege would convince the French Government of National Defense that Prussia could still be beaten. A prolonged campaign would also allow France time to reconstitute a new army and convince neutral powers to enter the war against Prussia. To Bismarck, Paris was the key to breaking the power of the intransigent republican leaders of France, ending the war in a timely manner, and securing peace terms favourable to Prussia.

Eventually, Wilhelm I overruled Moltke and ordered the field-marshal to consult with Bismarck for all future operations. Bismarck immediately ordered the city to be bombarded with new heavy caliber siege guns especially made for the siege by Krupp. The population began to suffer from starvation and with little hope of victory Trochu resigned as governor and left General Joseph Vinoy with 146,000 defenders to surrender on January 28 1871. The city sustained more damage in the 1870-1871 siege than in any other confict.

The Prussians had secured their victory in the Franco-Prussian War and on January 18 1871 at Versailles Wilhelm I was proclaimed German Emperor and the kingdoms of Bavaria, Wurttemberg, Saxony, the states of Baden and Hessen, and the free cities of Hamburg and Bremen were unified to create the German Empire under Kaiser Wilhelm I. The preliminary peace treaty was signed at Versailles and the final peace treaty was signed with the Treaty of Frankfurt on May 10 1871. Otto von Bismarck was able to secure Alsace-Lorraine from France as part of the German Empire under the Treaty of Frankfurt.

Another stipulation of the treaties was a German garrison to be left in Paris. This angered bitter Paris residents at the continued presence of German troops in the wake of defeat. Further resentment arose against the current French government and from April-May 1871 Paris workers and National Guards rebelled and established the Paris Commune.

References

• The Fall of Paris: The Siege and the Commune 1870-71; Alistair Horne ISBN 0330490362