The War of the Sixth Coalition (French: Guerre de la Sixième Coalition; December 1812 – May 1814), sometimes known in Germany as the Wars of Liberation (German: Befreiungskriege) saw a coalition of Austria, Prussia, Russia, Spain, the United Kingdom, Portugal, Sweden, Sardinia, and a number of German states defeat the First French Empire and force Napoleon into exile on Elba. Following the disastrous French invasion of Russia in 1812 in which they had been forced to support France, Prussia and Austria joined Russia, Britain, Sweden, Portugal and Spain against France.
The invasion of Russia cost the French many seasoned soldiers, so Napoleon took action to engage "Marie-Louises", young conscripts who were barely familiar with military affairs; they were called up from October 1813 to 1815. However, the constant warfare weakened the Coalition nations as well. The Russian military was particularly depleted after 1812, and Prussia also suffered a significant downgrade as a result of its losses in 1806–1807; nevertheless, it carried out large-scale reforms to improve the situation in the Prussian Army. Later, having encountered the Prussians in the Battle of Lützen, Napoleon would say: "These animals have learned something."
The war saw battles at Lützen, Bautzen, and Dresden. The even larger Battle of Leipzig was the largest battle fought in Europe until World War II. Despite experiencing a collapse in the army following the invasion of Russia, Napoleon managed to reorganise and stall the coalition, driving them out of Germany and compelling them to accept a truce. With their armies reorganized, the allies drove Napoleon out of Germany in 1813 and invaded France in 1814. Though it had experienced a second collapse after the battle of Leipzig, the French army managed to regroup and Napoleon struck the allies at the Battle of Brienne and the Battle of Saint-Dizier before his defeat at the Battle of La Rothiere, which motivated the coalition to march on Paris as they sensed Napoleon growing weaker. Napoleon then inflicted a series of successive defeats on the allies interrupted only by the (Battle of Laon), beginning with the Six Days' Campaign. After that, Napoleon launched an offensive against the army of Bohemia, driving them past Troyes. Following Marshal Marmont's pushing back of a second attempt by Prussia to march on Paris, Napoleon followed it up with the Battle of Craonne and the Battle of Reims, then driving back the Army of Bohemia until he lost momentum during the Battle of Arcis-sur-Aube where he was severely outnumbered. The Allies eventually overcame the French armies, occupied Paris after a stiff battle and forced Napoleon's first abdication in April 1814. Napoleon was exiled and the French monarchy was restored by the allies in the Bourbon Restoration. The Hundred Days began in 1815 when Napoleon escaped from his captivity on Elba and returned to power in France. He was defeated again for the final time at Waterloo, ending the Napoleonic Wars.
Background: Invasion of Russia
In June 1812, Napoleon invaded Russia to compel Emperor Alexander I to remain in the Continental System. The Grande Armée, consisting of as many as 650,000 men (roughly half of whom were French, with the remainder coming from allies or subject areas), crossed the Neman river on 24 June 1812. Russia proclaimed a Patriotic War, while Napoleon proclaimed a "Second Polish War". But against the expectations of the Poles, who supplied almost 100,000 troops for the invasion force, and having in mind further negotiations with Russia, he avoided restoring the old Polish-Lithuanian Commonwealth. Russian forces fell back, destroying everything potentially of use to the invaders until giving battle at Borodino (7 September) where the two armies fought a devastating battle. Despite the fact that France won a tactical victory, the battle was inconclusive. Following the battle the Russians withdrew, thus opening the road to Moscow. By 14 September, the French had occupied Moscow but found the city practically empty. Alexander I (despite having almost lost the war by Western European standards) refused to capitulate, leaving the French in the abandoned city of Moscow with little food or shelter (large parts of Moscow had burned down) and winter approaching. In these circumstances, and with no clear path to victory, Napoleon was forced to withdraw from Moscow.
So began the disastrous Great Retreat, during which the retreating army came under increasing pressure due to lack of food, desertions, and increasingly harsh winter weather, all while under continual attack by the Russian army led by Commander-in-Chief Mikhail Kutuzov, and other militias. Total losses of the Grand Army were at least 370,000 casualties as a result of fighting, starvation and the freezing weather conditions, and 200,000 captured. By November, only 27,000 fit soldiers re-crossed the Berezina river. Napoleon now left his army to return to Paris and prepare a defence of the Duchy of Warsaw against the advancing Russians. The situation was not as dire as it might at first have seemed; the Russians had also lost around 400,000 men, and their army was similarly depleted. However, they had the advantage of shorter supply lines and were able to replenish their armies with greater speed than the French, especially because Napoleon's losses of cavalry and wagons were irreplaceable.
Formation of the Sixth Coalition
Russia, Britain and Sweden form an alliance
At the beginning of 1812 Britain had already been at war with France since 1803, and had been fighting alongside the Portuguese and Spanish in the Peninsular War for more than three years. Russia and Sweden, which had opposed Napoleon up to 1807 and 1810 respectively, had been forced to join his Continental System against Britain, but continued to trade secretly with the British. On 9 January 1812, French troops suddenly occupied Swedish Pomerania, ostensibly to end trade between local smugglers and British merchants in violation of the Continental System. Swedish estates were confiscated and Swedish officers and soldiers were taken as prisoners.
In response, Charles John, formerly French Marshal Jean Baptiste Bernadotte, now the Crown Prince and Regent of Sweden, declared neutrality, and though Sweden was still at war with Britain, and Russia was its perennial enemy, he dispatched diplomats to London and St. Petersburg to create a new coalition against France. Sweden then signed the secret Treaty of Saint Petersburg with Russia against France and Denmark–Norway on 5 April 1812. On 18 July 1812, the Treaty of Örebro formally ended the wars between Britain and Sweden and Britain and Russia, forming the basis of coalition between Russia, Britain, and Sweden, though the exact parameters of a military alliance remained in negotiation throughout the winter of 1812–1813.
When Napoleon marched on Moscow in June 1812, neither Britain nor Sweden was able to give direct military support to Russia, though that same month the British, Portuguese and Spanish troops had advanced into central Spain, defeating the French at Salamanca and capturing Madrid, tying down 230,000 French-led troops. Britain also helped subsidize the Russian war effort while Charles John had struck up a friendship with Alexander, and gave him moral support, strategic and tactical advice on how to defeat the French, as well as valuable insights on Napoleon himself (having had much contact with Napoleon as a member of the extended Imperial Family). However Russia bore the brunt of the French onslaught on her territory alone. After the French Grande Armée retreated from Moscow on 18/19 October 1812 and suffered heavy casualties due to extreme cold, food shortages and repeated Russian attacks, Napoleon did not seem to be as invincible as before. On 14 December, the last French troops had left Russian soil, and Paris' allies were seriously considering rebellion and joining the Tsar's side.
The Convention of Tauroggen was a truce signed 30 December 1812 at Tauroggen between Generalleutnant Ludwig Yorck von Wartenburg on behalf of his Prussian troops (who had been compelled to augment the Grande Armée during the invasion of Russia), and by General Hans Karl von Diebitsch of the Imperial Russian Army. According to the Treaty of Tilsit (9 July 1807), Prussia had to support Napoleon's invasion of Russia. This resulted in some Prussians leaving their army to avoid serving the French, like Carl von Clausewitz, who joined Russian service. When Yorck's immediate French superior Marshal MacDonald, retreated before the corps of Diebitsch, Yorck found himself isolated. As a soldier his duty was to break through, but as a Prussian patriot his position was more difficult. He had to judge whether the moment was favorable for starting a war of liberation; and, whatever might be the enthusiasm of his junior staff-officers, Yorck had no illusions as to the safety of his own head, and negotiated with Clausewitz. The Convention of Tauroggen armistice, signed by Diebitsch and Yorck, "neutralized" the Prussian corps without consent of their king. The news was received with the wildest enthusiasm in Prussia, but the Prussian Court dared not yet throw off the mask, and an order was despatched suspending Yorck from his command pending a court-martial. Diebitsch refused to let the bearer pass through his lines, and the general was finally absolved when the Treaty of Kalisch (28 February 1813) definitely ranged Prussia on the side of the Allies.