Franco-Prussian War
Part of the wars of German unification
Clockwise from top: Prussian infantry at the battle of Spicheren ; Jeanniot's La ligne de feu (1886), depicting the Battle of Mars-La-Tour ; Werner's depiction of the capitulation of Sedan ; Neuville's "Last bullets" depicting the Battle of Bazeilles.
Date 19 July 1870 – 10 May 1871 (296 days) Location France and Prussia Result German victory Territorial changes Treaty of Frankfurt Formation of the German Empire German annexation of Alsace-Lorraine Formation of the French Third Republic
Belligerents
Second French Empire (until September 4, 1870)	North German Confederation:  Prussia (leading member of the North German Confederation) Baden  Bavaria Württemberg
French Third Republic (starting on September 4, 1870)	German Empire (starting on January 18, 1871)
Commanders and leaders
Napoleon III (POW) François Achille Bazaine  (POW) Louis Jules Trochu Patrice de Mac-Mahon, duc de Magenta Léon Gambetta Giuseppe Garibaldi	Wilhelm I Otto von Bismarck Helmuth von Moltke Karl Friedrich von Steinmetz Prince Friedrich Karl Crown Prince Friedrich Albrecht von Roon
Strength
492,585 active[1] 417,366 Garde Mobile[2]	300,000 regular 900,000 reserves and Landwehr[3]
Casualties and losses
138,871 dead[4] 143,000 wounded 474,414 captured 756,285 total casualties[5]	28,208 dead 88,488 wounded 116,696 total casualties[6]

The Franco-Prussian War or Franco-German War, often referred to in France as the 1870 War^[7] (19 July 1870 – 10 May 1871), was a conflict between the Second French Empire and the Kingdom of Prussia. Prussia was aided by the North German Confederation, of which it was a member, and the South German states of Baden, Württemberg and Bavaria. The complete Prussian and German victory brought about the final unification of Germany under King Wilhelm I of Prussia. It also marked the downfall of Napoleon III and the end of the Second French Empire, which was replaced by the French Third Republic. As part of the settlement, the territory of Alsace and part of Lorraine was taken by Prussia to become a part of Germany, and it remained so until the end of World War I when it was returned to France in the Treaty of Versailles.

The conflict was a culmination of years of tension between the two nations, which finally came to a head over the issue of a Hohenzollern candidate for the vacant Spanish throne, following the deposition of Isabella II in 1868. The public release of the Ems Dispatch, which played up alleged insults between the Prussian king and the French ambassador, inflamed public opinion on both sides. France mobilized, and on 19 July 1870 declared war on Prussia only, but the other German states quickly joined on Prussia's side.

It soon became evident that the Prussian and German forces were superior, due in part to their efficient use of railways and the better Krupp steel artillery. Prussia had the fourth densest rail network in the world; France had the fifth.^[8] A series of swift Prussian and German victories in eastern France culminated in the Battle of Sedan, at which Napoleon III was captured with his whole army on 2 September. Yet this did not end the war, as the Third Republic was declared in Paris on 4 September 1870, and French resistance continued under the Government of National Defence and later Adolphe Thiers.

Over a five-month campaign, the German armies defeated the newly recruited French armies in a series of battles fought across northern France. Following a prolonged siege, Paris fell on 28 January 1871. The siege is also notable for the first use of anti-aircraft artillery, a Krupp piece built specifically to shoot down the hot air balloons being used by the French as couriers. Ten days earlier, the German states had proclaimed their union under the Prussian king, uniting Germany as a nation-state, the German Empire. The final Treaty of Frankfurt was signed 10 May 1871, during the time of the Paris Commune uprising of 1871.

Causes[link]

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The causes of the Franco-Prussian War are deeply rooted in the events surrounding the balance of power in Europe after the Napoleonic Wars. France and Prussia had been combatants, with France on the losing side and Napoleon I exiled to St. Helena. The war was increasingly likely as France would not tolerate its gradual loss of status and geopolitical advantage due to Prussia's increasing influence in Germany, as Otto von Bismarck noted in his book, after being forced to resign from the role of Chancellor, that "I knew that a Franco-Prussian War must take place before a united Germany was formed."^[9] French Emperor Napoleon III and Prime Minister Émile Ollivier's eagerness to relieve France from internal political convulsions also contributed to France's declaration of war on Prussia.^[10]

In addition, Otto von Bismarck goaded the French into declaring war by altering a telegram sent by William I. Releasing the Ems Telegram to the public, Bismarck made it sound as if the king had treated the French envoy in a demeaning fashion. Six days later, France declared war on Prussia.

Opposing forces[link]

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The French Army comprised approximately 400,000 regular soldiers, some of them veterans of previous French campaigns in the Crimean War, Algeria, the Franco-Austrian War in Italy, and in Mexico in support of the Second Mexican Empire. The infantry were equipped with the breech-loading Chassepot rifle, one of the most modern mass-produced firearms in the world at the time. With a rubber ring seal and a smaller bullet, the Chassepot had a maximum effective range of some 1,500 metres (4,900 ft) with a short reload time. The artillery was equipped with rifled, muzzle-loaded Lahitte "4-pounder" (actual weight of shot: 4 kg/8.8 lb) guns. In addition, the army was equipped with a precursor to the machine-gun: the mitrailleuse, which can unleash significant, concentrated firepower, with a weakness of having short range and relative immobility and thus easily overrun. Mitrailleuse was mounted on an artillery gun carriage and grouped in batteries in a similar fashion to cannon. The army was nominally led by Napoleon III with Marshals Francois Achille Bazaine, Patrice de Mac-Mahon, and Jules Trochu among others.

The Prussian Army was composed not of regulars but conscripts. Service was compulsory for all of the men of military age, and thus Prussia and its North and South German allies could mobilise and field some 1.2 million soldiers in time of war. The sheer number of soldiers available made mass-encirclement and destruction of enemy formations advantageous. The army was still equipped with the "needle-gun" Dreyse rifle of Battle of Königgrätz fame, which was by this time showing the age of its 25 year old design. The deficiencies of the needle-gun were more than compensated for by the famous Krupp 6-pounder (3 kg) steel breech-loading cannons being issued to Prussian artillery batteries. Firing a contact-detonated shell filled with zinc balls and explosives, the Krupp gun had a range of 4,500 metres (14,800 ft) and blistering rate of fire compared to the French bronze muzzle loading cannon. The Prussian army was commanded by Field-Marshal Helmuth von Moltke and the Prussian General Staff. The Prussian army was unique in Europe for having the only General Staff in existence, whose sole purpose was to direct operational movement, organise logistics and communications and develop the overall war strategy. In practice, a chief of staff was a much more important figure in the Prussian Army than in any other army, because he had the right to appeal against his superior to the commander of the next highest formation. Thus, for example, the Crown Prince was unable to contradict the advice of his Chief of Staff, General Leonhard, Count von Blumenthal, for fear of a direct appeal (in this case) to his father, the King.

Given that France maintained a strong standing army, and that Prussia and the other German states would need weeks to mobilise their conscript armies, the French held the initial advantage of troop numbers and experience. French tactics emphasised the defensive use of the Chassepot rifle in trench-warfare style fighting; German tactics emphasised encirclement battles and using artillery offensively whenever possible.

Summary of military events[link]

German mobilization contrasted with confusion and delay on the French side. Germany was able to deliver 380,000 troops to the forward zone within 18 days of the start of July 14 mobilization, while many French units reached the front either late or with inadequate supplies. The German and French armies that then confronted each other were both grouped into right and left wings. After suffering a check at the Battle of Wörth on August 6, 1870, the commander of the French right (south) wing, Marshal Patrice MacMahon, retreated westward. That same day, about 40 miles (64 km) to the northwest, the commander of the French left wing, Marshal Achille Bazaine, was dislodged from near Saarbrücken and fell back westward to the fortress of Metz. His further retreat was checked by the German right wing in two blundering battles on August 16 and 18, respectively (the Battles of Mars-la-Tour and Gravelotte), and he then took refuge behind the defenses of Metz until forced by starvation to surrender on October 29.

The French right wing, commanded by MacMahon and accompanied by Napoleon III himself, attempted to relieve Bazaine but was itself surrounded and trapped by the Germans in the disastrous Battle of Sedan on August 31. Encircled, the 83,000 French troops with Napoleon III and MacMahon surrendered on September 2. Since Bazaine's army was still bottled up in Metz, the result of the war was virtually decided by this surrender. French resistance was carried on against desperate odds by a new government of national defense, which assumed power in Paris on September 4, 1870, and proclaimed the deposition of the emperor and the establishment of the Third Republic. On September 19 the Germans began to besiege Paris. Jules Favre, foreign minister in the new government, went to negotiate with Bismarck, but the negotiations were broken off when he found that Germany demanded both Alsace and Lorraine regions. Léon Gambetta, the leading figure in the provisional government, organized new French armies in the countryside after escaping from besieged Paris in a balloon. These engaged but could not defeat the German forces. Bazaine capitulated at Metz with his 140,000 troops intact on October 27, and Paris surrendered on January 28, 1871.

French Army incursion[link]

Preparations for the offensive[link]

Map of German and French armies near their common border on 31 July 1870

On 28 July 1870 Napoleon III left Paris for Metz and assumed command of the newly titled Army of the Rhine, some 202,448 strong and expected to grow as the French mobilization progressed.^[11] Marshal MacMahon took command of I Corps (4 infantry divisions) near Wissembourg, Marshal François Canrobert brought VI Corps (4 infantry divisions) to Châlons-sur-Marne in northern France as a reserve and to guard against a Prussian advance through Belgium.

A pre-war plan laid out by the late Marshal Adolphe Niel called for a strong French offensive from Thionville towards Trier and into the Prussian Rhineland. This plan was discarded in favour of a defensive plan by Generals Charles Frossard and Bartélemy Lebrun, which called for the Army of the Rhine to remain in a defensive posture near the German border and repel any Prussian offensive. As Austria along with Bavaria, Württemberg and Baden were expected to join in a revenge war against Prussia, I Corps would invade the Bavarian Palatinate and proceed to "free" the South German states in concert with Austro-Hungarian forces. VI Corps would reinforce either army as needed.^[12]

Unfortunately for General Frossard's plan, the Prussian army was mobilizing far more rapidly than expected. The Austro-Hungarians, still smarting after their defeat by Prussia in the Austro-Prussian War, were treading carefully before stating that they would only commit to France's cause if the southern Germans viewed the French positively. This did not materialize as the South German states had come to Prussia's aid and were mobilizing their armies against France.^[13]

Occupation of Saarbrücken[link]

French Lancers and Cuirassiers guarding captured Bavarian soldiers

Napoleon III was under immense domestic pressure to launch an offensive before the full might of Moltke's forces was mobilized and deployed. Reconnaissance by General Frossard had identified only the Prussian 16th Infantry Division guarding the border town of Saarbrücken, right before the entire Army of the Rhine. Accordingly, on 31 July the Army marched forward toward the Saar River to seize Saarbrücken.^[14]

General Frossard's II Corps and Marshal Bazaine's III Corps crossed the German border on 2 August, and began to force the Prussian 40th Regiment of the 16th Infantry Division from the town of Saarbrücken with a series of direct attacks. The Chassepot rifle proved its worth against the Dreyse rifle, with French riflemen regularly outdistancing their Prussian counterparts in the skirmishing around Saarbrücken. However the Prussians resisted strongly, and the French suffered 86 casualties to the Prussian 83 casualties. Saarbrücken also proved to be a major obstacle in terms of logistics. Only one railway there led to the German hinterland but could be easily defended by a single force, and the only river systems in the region ran along the border instead of inland.^[15] While the French hailed the invasion as the first step towards the Rhineland and later Berlin, General Le Bœuf and Napoleon III were receiving alarming reports from foreign news sources of Prussian and Bavarian armies massing to the southeast in addition to the forces to the north and northeast.^[16]

Moltke had indeed massed three armies in the area—the Prussian First Army with 50,000 men, commanded by General Karl Von Steinmetz opposite Saarlouis, the Prussian Second Army with 134,000 men commanded by Prince Friedrich Karl opposite the line Forbach–Spicheren, and the Prussian Third Army with 120,000 men commanded by Crown Prince Friedrich Wilhelm, poised to cross the border at Wissembourg.^[17]

Prussian Army advance[link]

Battle of Wissembourg[link]

French soldiers in the Franco-Prussian War 1870–71

Upon learning from captured Prussian soldiers and a local area police chief that the Second Army was just 30 miles (48 km) from Saarbrücken near the town of Wissembourg, General Le Bœuf and Napoleon III decided to retreat to defensive positions. General Frossard, without instructions, hastily withdrew the elements of Army of the Rhine in Saarbrücken back to Spicheren and Forbach.^[18]

Marshal MacMahon, now closest to Wissembourg, left his four divisions spread 20 miles (32 km) apart in diameter to react to any Prussian invasion. This organization of forces was due to a lack of supplies, forcing each division to seek out basic provisions along with the representatives of the army supply arm that was supposed to aid them. What made a bad situation much worse was the conduct of General Auguste-Alexandre Ducrot, commander of MacMahon's 1st Division. He told General Abel Douay, commander of MacMahon's 2nd Division, on 1 August that "The information I have received makes me suppose that the enemy has no considerable forces very near his advance posts, and has no desire to take the offensive".^[19] Two days later, he told MacMahon that he had not found "a single enemy post [...] it looks to me as if the menace of the Bavarians is simply bluff". Even though Ducrot shrugged off the possibility of an attack by the Germans, MacMahon still tried to warn the other divisions of his army, without success.^[20]

The first action of the Franco-Prussian War took place on 4 August 1870. This bloody little battle saw the unsupported division of General Douay of I Corps, with some attached cavalry, which was posted to watch the border, attacked in overwhelming but poorly coordinated fashion by the German 3rd Army. As the day wore on, elements of one Bavarian and two Prussian Corps became embroiled in the fight, and were aided by Prussian artillery which blasted holes in the defenses of the town. Douay held a very strong position initially thanks to the accurate long range fire of the Chassepots, but his force was too thinly stretched to hold it. Douay was killed in the late morning when a caisson of the divisional mitrailleuse battery exploded near him. No matter who took his place, the encirclement of the town by the enemy had put the entire division in peril.^[21]

The fighting within the town had become extremely intense, becoming a door to door battle of survival. Despite a never ending attack of Prussian infantry, the soldiers of the 2nd Division kept to their positions.The people of the town of Wissembourg finally surrendered to the Germans. Those who did not surrender retreated westward, leaving behind 1,000 captured men and all of their remaining ammunition.^[22] The Prussians seemed poised to capitalize on these happenings, and the French appeared still woefully unaware of the now forming Prussian juggernaut.

Battle of Spicheren[link]

Map of Prussian and German offensive, 5 August and 6 August 1870

The Battle of Spicheren, on 5 August, was the second of three critical French defeats. Moltke had originally planned to keep Bazaine's army on the Saar River until he could attack it with the 2nd Army in front and the 1st Army on its left flank, while the 3rd Army closed towards the rear. The aging General Karl Von Steinmetz made an overzealous, unplanned move, leading the 1st Army south from his position on the Moselle. He moved straight toward the town of Spicheren, cutting off Prince Frederick Charles from his forward cavalry units in the process.^[23]

On the French side, planning after the disaster at Wissembourg had become essential. General Le Bœuf, flushed with anger, was intent upon going on the offensive over the Saar and countering their loss. However, planning for the next encounter was more based upon the reality of unfolding events rather than emotion or pride, as Intendant General Wolff told him and his staff that supply beyond the Saar would be impossible. Therefore, the armies of France would take up a defensive position that would protect against every possible attack point, but also left the armies unable to support each other.^[24]

While the French army under General MacMahon engaged the German 3rd Army at the Battle of Wörth, the German 1st Army under Steinmetz finished their advance west from Saarbrücken. A patrol from the German 2nd Army under Prince Friedrich Karl of Prussia spotted decoy fires close and Frossard's army farther off on a distant plateau south of the town of Spicheren, and took this as a sign of Frossard's retreat. Ignoring Moltke's plan again, both German armies attacked Frossard's French 2nd Corps, fortified between Spicheren and Forbach.^[25]

The French were unaware of their numerical superiority at the beginning of the battle as the German 2nd Army did not attack all at once. Treating the oncoming attacks as merely skirmishes, Frossard did not request additional support from other units. By the time he realized what kind of a force he was opposing, it was too late. Seriously flawed communications between Frossard and those in reserve under Bazaine slowed down so much that by the time the reserves received orders to move out to Spicheren, German soldiers from the 1st and 2nd armies had charged up the heights.^[26] Because the reserves had not arrived, Frossard erroneously believed that he was in grave danger of being outflanked as German soldiers under General von Glume were spotted in Forbach. Instead of continuing to defend the heights, by the close of battle after dusk he retreated to the south. The German casualties were relatively high due to the advance and the effectiveness of the chassepot rifle. They were quite startled in the morning when they had found out that their efforts were not in vain–Frossard had abandoned his position on the heights.^[27]

Battle of Wörth (known also as Fröschwiller or Reichshoffen)[link]

Aimé Morot's La bataille de Reichshoffen, 1887

The two armies clashed again two days later on 6 August 1870 near Wörth in the town of Fröschwiller, less than ten miles (16 km) from Wissembourg. The German 3rd army had drawn reinforcements which brought its strength up to 140,000 troops. The French had also been reinforced, but their recruitment was slow, and their force numbered only 35,000. Although badly outnumbered, the French defended their position just outside Fröschwiller. By afternoon, both sides had suffered about 10,000 casualties, and the French army was too battered to continue resisting. To make matters even more dire for the French, the Germans had taken the town of Fröschwiller which sat on a hilltop in the centre of the French line. Having lost any hope for victory and facing a massacre, the French army disengaged and retreated in a westerly direction, hoping to join other French forces on the other side of the Vosges mountains. The German 3rd army did not pursue the withdrawing French. It remained in Alsace and moved slowly south, attacking and destroying the French defensive garrisons in the vicinity.

The battle of Wörth was the first major battle of the Franco-German war, with more than 100,000 troops in the battlefield. It was also one of the first clashes where troops from various German states (Prussians, Badeners, Bavarians, Saxons, etc.) fought jointly. These facts have led some historians to call the battlefield of Wörth the "cradle of Germany". It was not without cost, however, as Prussia lost 10,500 to death or wounds. MacMahon's situation was even more dire, as French casualties reached 19,200 killed, wounded or captured.^[28]

Battle of Mars-La-Tour[link]

The Prussian 7th Cuirassiers charge the French guns at the Battle of Mars-La-Tour, 16 August 1870.

With the Prussian army now steamrolling, 130,000 French soldiers were bottled up in the fortress of Metz following several defeats at the front. Their attempt to leave Metz in order to link up with French forces at Châlons was spotted by a Prussian cavalry patrol under Major Oskar von Blumenthal. Four days after their retreat, on 16 August a grossly outnumbered Prussian force of 30,000 men of III Corps (of the 2nd Army) under General Konstantin von Alvensleben, found the French Army near Vionville, east of Mars-la-Tour.

Despite odds of four to one, the III Corps launched a risky attack. The French were routed and the III Corps captured Vionville, blocking any further escape attempts to the west. Once blocked from retreat, the French in the fortress of Metz had no choice but to engage in a fight that would see the last major cavalry engagement in Western Europe. The battle soon erupted, and III Corps was shattered by incessant cavalry charges, losing over half its soldiers. Meanwhile, French suffered equivalent losses of 16,000 soldiers, but still enjoyed huge numerical superiority.

On 16 August, the French had a chance to sweep away the key Prussian defense, and to escape. Two Prussian corps attacked the French advanced guard thinking that it was the rearguard of the retreat of the French Army of the Meuse. Despite this misjudgment the two Prussian corps held the entire French army for the whole day. Outnumbered 5 to 1, the extraordinary élan of the Prussians prevailed over gross indecision by the French. The French had lost the opportunity to win a decisive victory.^[29]

Battle of Gravelotte[link]

The Battle of Gravelotte, or Gravelotte-St. Privat, was the largest battle during the Franco-Prussian War. It was fought about six miles (10 km) west of Metz, Lorraine, France where on the previous day, having intercepted the French army's retreat to the west at the Battle of Mars-La-Tour, the Prussians were now closing in to complete the destruction of the French forces.

The combined German forces, under Field Marshal Count Helmuth von Moltke, were the Prussian First and Second Armies of the North German Confederation numbering about 210 infantry battalions, 133 cavalry squadrons, and 732 heavy cannon totaling 188,332 officers and men. The French Army of the Rhine, commanded by Marshal François-Achille Bazaine, numbering about 183 infantry battalions, 104 cavalry squadrons, backed by 520 heavy cannon, totaling 112,800 officers and men, dug in along high ground with their southern left flank at the town of Rozerieulles, and their northern right flank at St. Privat.

On 18 August, the battle began when at 08:00 Moltke ordered the First and Second Armies to advance against the French positions. By 12:00, General Manstein opened up the battle before the village of Amanvillers with artillery from the 25th Infantry Division. But the French had spent the night and early morning digging trenches and rifle pits while placing their artillery and their mitrailleuses in concealed positions. Finally aware of the Prussian advance, the French opened up a massive return fire against the mass of advancing Germans. The battle at first appeared to favor the French with their superior Chassepot rifle. However, the Prussian artillery was superior with the all-steel Krupp breech-loading gun.

Juliusz Kossak, Battle of Gravelotte, depicting the Prussians at Gravelotte, 1871

By 14:30, General Steinmetz, the commander of the First Army, unilaterally launched his VIII Corps across the Mance Ravine in which the Prussian infantry were soon pinned down by murderous rifle and mitrailleuse fire from the French positions. At 15:00, the massed guns of the VII and VIII Corps opened fire to support the attack. But by 16:00, with the attack in danger of stalling, Steinmetz ordered the VII Corps forward, followed by the 1st Cavalry Division.

By 16:50, with the Prussian southern attacks in danger of breaking up, the Prussian 3rd Guards Infantry Brigade of the Second Army opened an attack against the French positions at St-Privat which were commanded by General Canrobert. At 17:15, the Prussian 4th Guards Infantry Brigade joined the advance followed at 17:45 by the Prussian 1st Guards Infantry Brigade. All of the Prussian Guard attacks were pinned down by lethal French gunfire from the rifle pits and trenches. At 18:15 the Prussian 2nd Guards Infantry Brigade, the last of the 1st Guards Infantry Division, was committed to the attack on St. Private while Steinmetz committed the last of the reserves of the First Army across the Mance Ravine. By 18:30, a considerable portion of the VII and VIII Corps disengaged from the fighting and withdrew towards the Prussian positions at Rezonville.

With the defeat of the First Army, Prince Frederick Charles ordered a massed artillery attack against Canrobert's position at St. Private to prevent the Guards attack from failing too. At 19:00 the 3rd Division of Fransecky's II Corps of the Second Army advanced across Ravine while the XII Corps cleared out the nearby town of Roncourt and with the survivors of the 1st Guards Infantry Division launched a fresh attack against the ruins of St. Privat. At 20:00, the arrival of the Prussian 4th Infantry Division of the II Corps and with the Prussian right flank on Mance Ravine, the line stabilised. By then, the Prussians of the 1st Guards Infantry Division and the XII and II Corps captured St. Private forcing the decimated French forces to withdraw. With the Prussians exhausted from the fighting, the French were now able to mount a counter-attack. General Bourbaki, however, refused to commit the reserves of the French Old Guard to the battle because, by that time, he considered the overall situation a 'defeat'.

By 22:00, firing largely died down across the battlefield for the night. The next morning, the French Army of the Rhine, rather than resume the battle with an attack of its own against the battle-weary German armies, retreated to Metz where they were besieged and forced to surrender two months later.

The casualties were horrible, especially for the attacking Prussian forces. A grand total of 20,163 German troops were killed, wounded or missing in action during the August 18 battle. The French losses were 7,855 killed and wounded along with 4,420 prisoners of war (half of them were wounded) for a total of 12,275. While most of the Prussians fell under the French Chassepot rifles, most French fell under the Prussian Krupp shells. In a breakdown of the casualties, Frossard's II Corps of the Army of the Rhine suffered 621 casualties while inflicting 4,300 casualties on the Prussian First Army under Steinmetz before the Pointe du Jour. The Prussian Guards Infantry Divisions losses were even more staggering with 8,000 casualties out of 18,000 men. The Special Guards Jäger lost 19 officers, a surgeon and 431 men out of a total of 700. The 2nd Guards Infantry Brigade lost 39 officers and 1,076 men. The 3rd Guards Infantry Brigade lost 36 officers and 1,060 men. On the French side, the units holding St. Private lost more than half their number in the village.

Siege of Metz and the Battle of Sedan[link]

With the defeat of Marshal Bazaine's Army of the Rhine at Gravelotte, the French were forced to retire to Metz where they were besieged by over 150,000 Prussian troops of the First and Second Armies. The further crushing French loss was sealed when the 180,000 soldiers surrendered on 27 October.

Franco-Prussian war of 1870. Defence of Metz by the French Army.

As a result of the defeat, Napoleon III, along with Field Marshal MacMahon, formed the new French Army of Châlons to march on to Metz to rescue Bazaine. With Napoleon III personally leading the army with Marshal MacMahon in attendance, they led the Army of Châlons in a left-flanking march northeast towards the Belgian border in an attempt to avoid the Prussians before striking south to link up with Bazaine.

Napoleon III and Bismarck talk after Napoleon's capture at the Battle of Sedan by Wilhelm Camphausen