quality:corruption
Government of National Defence

When news of Napoleon III's surrender at Sedan arrived in Paris, the Second Empire was overthrown by a popular uprising. On 4 September, Jules Favre, Léon Gambetta, and General Louis-Jules Trochu proclaimed a provisional government called the Government of National Defence and a Third Republic. After the German victory at Sedan, most of the French standing army was either besieged in Metz or held prisoner by the Germans, who hoped for an armistice and an end to the war. Bismarck wanted an early peace but had difficulty finding a legitimate French authority with whom to negotiate. The Emperor was a captive and the Empress in exile, but there had been no abdication de jure and the army was still bound by an oath of allegiance to the defunct imperial regime; on the other hand, the Government of National Defence had no electoral mandate.

Prussia's intention was to weaken the political position of France abroad. The defensive position of the new French authorities, who offered Germany an honorable peace and reimbursement of the costs of the war, was presented by Prussia as aggressive; they rejected the conditions put forward and demanded the annexation of the French provinces of Alsace and part of Lorraine. Bismarck was dangling the Emperor over the republic's head, calling Napoleon III "the legitimate ruler of France" and dismissing Gambetta's new republic as no more than " un coup de parti " ("a partisan coup"). This policy was to some extent successful; the European press discussed the legitimacy of the French authorities, and Prussia's aggressive position was to some extent understood. Only the United States and Spain recognized the Government of National Defence immediately after the announcement; other countries refused to do this for some time.

The question of legitimacy is rather strange for France after the coup d'état of 1851, since Louis-Napoleon himself only overthrew the Second Republic and rose to the imperial throne by means of a coup d'état.

The Germans expected to negotiate an end to the war, but while the republican government was amenable to war reparations or ceding colonial territories in Africa or Southeast Asia, it would go no further. On behalf of the Government of National Defense, Favre declared on 6 September that France would not "yield an inch of its territory nor a stone of its fortresses". The republic then renewed the declaration of war, called for recruits in all parts of the country, and pledged to drive the German troops out of France by a guerre à outrance ('overwhelming attack'). The Germans continued the war, yet could not pin down any proper military opposition in their vicinity. As the bulk of the remaining French armies was digging in near Paris, the German leaders decided to put pressure upon their enemy by attacking there. By 15 September, German troops had reached the outskirts and Moltke issued the orders to surround the city. On 19 September, the Germans surrounded it and erected a blockade, as already established at Metz, completing the encirclement on 20 September. Bismarck met Favre on 18 September at the Château de Ferrières and demanded a frontier immune to a French war of revenge, which included Strasbourg, Alsace, and most of the Moselle department in Lorraine, of which Metz was the capital. In return for an armistice for the French to elect a National Assembly, Bismarck demanded the surrender of Strasbourg and the fortress city of Toul. To allow supplies into Paris, one of the perimeter forts had to be handed over. Favre was unaware that Bismarck's real aim in making such extortionate demands was to establish a durable peace on Germany's new western frontier, preferably by a peace with a friendly government, on terms acceptable to French public opinion. An impregnable military frontier was an inferior alternative to him, favoured only by the militant nationalists on the German side.

When the war had begun, European public opinion heavily favoured the Germans; many Italians attempted to sign up as volunteers at the Prussian embassy in Florence and a Prussian diplomat visited Giuseppe Garibaldi in Caprera. Bismarck's demand that France surrender sovereignty over Alsace caused a dramatic shift in that sentiment in Italy, which was best exemplified by the reaction of Garibaldi soon after the revolution in Paris, who told the Movimento of Genoa on 7 September 1870 that "Yesterday I said to you: war to the death to Bonaparte. Today I say to you: rescue the French Republic by every means." Garibaldi went to France and assumed command of the Army of the Vosges, with which he operated around Dijon until the end of the war.

The energetic actions of a part of the government (delegation) in Tours under Gambetta's leadership led to significant success in the formation of a new army. In less than four months, with persistent battles at the front, eleven new corps were formed (Nos. XVI–XXVI). The average success of the formation was equal to six thousand infantrymen and two batteries per day. This success was achieved despite the fact that the military industry and warehouses were concentrated mainly in Paris; all supplies in the province—chiefs, weapons, camps, uniforms, ammunition, equipment, baggage—had to be improvised anew. Many branches of the military industry were re-established in the province. Freedom of communication with foreign markets brought significant benefits; it was possible to make large purchases on foreign markets, mainly English, Belgian, and American. The artillery created by Gambetta in four months—238 batteries—was one and a half times larger than the artillery of imperial France. In the end, eight corps participated in the battles, and three were ready only by the end of January, when a truce was already concluded.

While the Germans had a 2:1 numerical advantage before Napoleon III's surrender, this French recruitment gave them a 2:1 or 3:1 advantage. The French more than tripled their forces during the war, while the Germans did not increase theirs as much; the number of 888,000 mobilized by the North German Union in August increased by only 2% after 3 + 1 ⁄ 2 months, and by the end of the war, six months later, only by 15%, which did not even balance the losses incurred. Prussia was completely unaware of the feverish activity of permanent mobilization. This disparity in forces created a crisis for the Germans at the front in November 1870, which only the release of the large forces besieging the fortress of Metz allowed them to overcome.