The Army of Châlons () was a French military formation that fought during the Franco-Prussian War of 1870. Formed in the camp of Châlons on August 17, 1870, from elements of the Army of the Rhine which the formation was issued from, the Army of Châlons was engaged in combats of Beaumont and Sedan while disappearing during the capitulation of September 2, 1870.
Creation of the army
Following the unfortunate adventures of the Army of the Rhine () in the beginning of August at Wissembourg, Wörth, Forbach, Empress Eugénie designated régente, summoned the two chambers on August 9, 1870. Three days later, the Emperor decided to confine the command of the Army of the Rhine to Marshal Bazaine.
On August 17, the Emperor was at Châlons and, during a reduced war council, the latter decided the nomination of Bazaine as généralissime of the French armed forces, of général Trochu as governor of Paris and de MacMahon as commander of the Army of Châlons. Accordingly, this new army constituted of available elements, composed the 1st Corps, which joined the camp of Châlons between August 14 and 17, the 5th Corps of général Failly, the 7th Corps of général Douay, and the 12th Corps recently formed, constituted from infantry regiments still available, marching regiments formed by the 4 battalions left in the depot and regiments of the Guard. Accordingly, the four armed corps were assembled at Reims on August 20, 1870.
Chronology of operations
While Mac Mahon wished to retreat on Paris in order to reconstitute his army, consultations convinced him of rescuing Bazaine which unfolded on Metz following new engagements at Rezonville and Saint-Privat on August 16 and 18. Mac Mahon decided on August 23 to leave Reims and marched towards the north-east in order to pass Meuse between Sedan and Verdun.
While the four corps of Mac Mahon made way north-east, the German Army, strong of previous successes reorganized in two groups: In front of Metz, the Ist Army, four corps of the IInd and one division. Opposed to the Army of Châlons, the IIIrd Army, constituted of five corps, was associated to a new army, the Army of the Meuse or IV army, composed of three army corps and four cavalry divisions. The ensemble represented 188000 fantassins, 36000 cavaliers and more than 810 pieces of artillery.
The progression of the French Army was slow, and the latter was caught up by the German troops before reaching Meuse. On the 29, following a first confrontation at Nouart with the XII Corps Saxon, the 5th corps of de Failly garrisoned at Beaumont. Around noon time, on August 30, the first shells hit the camp. Three German armed corps engaged the troops of Beaumont: the I. Bayerischen Korps on the left, the IV. Armee-Korps (Prussian) at the center and the sächsisches XII. Armee-Corps to the right. Despite the resistance of the infantry and the relaunching of combats at Mouzon with the unfortunate heroic charge of the 5th Cuirassiers, the corps of de Failly was defeated and had to retreat on Sedan.
The battle of Beaumont had for consequence the renunciation of Marshal Mac Mahon to come and rescue Bazaine at Metz. Contrary, he unfolded since August 30 the different corps on the cities of Bazeilles and Sedan.
thumb|180px|Général Wimpffen, commander-in-chief of the Army of Châlons at Sedan. On the 31st, the I. Bayerischen Korps of général Von der Tann confronted the 12th Corps while apprehending the pont de chemin de fer which was along Meuse south of Bazeilles. The next day, on September 1, 1870, the IIIrd and IV German corps attacked the ensemble of the armies of Mac Mahon positioned in the two cities. The marshal was wounded while searching to join the command of the 12th Corps, général Lebrun, attacked by the Ist Corps Bavarois at Bazeilles. First replaced by général Ducrot, the command of the army was replaced, under orders of the minister of war, to général Winpffen, recently named at the head of the 5th Army Corps. The German Army finished by encircling the ensemble of the army which unfolded on the citadelle in Sedan. On the morning of September 2, the capitulation was in effect. This battle witnessed the disappearing of the Army of Châlons, which consisted the loss of 124.000 men for France.
Composition and order of battle
On August 23, 1870, the Army of Châlons was constituted of four Army Corps along with artillery and cavalry reserves, consisting of 105.000 fantassins, 14.709 cavaliers, 393 pieces of artillery and 76 mitrailleuses. Lieutenant-colonel Rousset gave a, estimative decomposition by grand units: