Final defeat in 1813 and 1814 of Napoleon
A victory only against Prussia, even if decisive, wasn't adequate as Napoleon found out when a postponed Treaty of Danzig [originally intended for Christmas Day 1812] was about to be signed just as Prussian fortresses in Silesia froze and starved. News of Russian prisoners being transferred to Britain and Sweden in exchange for assistance and insistence of Poland's surrender of territories threatened Napoleon to restart the Prussian campaign. Angered, Napoleon restarted the campaign during the winter, but a lack of winter clothing and the prolonged siege of Prussian fortresses stopped planning temporarily. Then, bad news from Spain came with defeat in the Pyrenees following a failed offensive into Catalonia to defeat the remains of the Spanish Army and its encirclement supported by guerrillas and British troops. Under the command of Marshal Davout, the poorly supplied and outnumbered army under his command was defeated at Madrid and the Ebro River in October and retreated without the marshal, who fell into the Ebro River and was captured. The Pyrenees were nearly recaptured in December 1812 by Spain, although they failed to encircle instead. Napoleon was determined to make good use of some reprieve to deal with Spain. Meanwhile, the unexpected news from Prussia were partly the result of Davout's defeat and a crushed revolt in Poland. The truce was to be maintained for one year, in fact, it was only for five or four months.
Napoleon decided to make his move against Prussia first after noticing that Prussia would reject his peace offer in the long run by request and refused the deal. Then, he decided to leave Poland with his Grand Army while the Prussians never surrendered unconditionally to Napoleon after a first attempt due to revolting and the French retreat. British ships made it difficult for many conscripts to fight the Sixth Coalition, but the first 1813 French offensive against Spanish troops began on 20 April and Prussia stabbed Napoleon at the back by retaking fortresses and routing a French Army mostly foreign in ethnicity and demotivated fighting against the remains of the Prussians. Many prisoners of war returned to their nation's side during the liberation of Silesia, Pomerania and West Prussia from 12 May to 20 July from Danzig to Breslau and Berlin was recaptured by 31 July. Another concern was the loss of Russia's offensive capability and the Austrian defeat of remaining Napoleonic German states, with the Austrian Army defeating Wurttemberg's troops and causing former Prussians to fight Napoleon again, prompting a French counteroffensive as a crossing of the Rhine was made in early June 1813. Although the Austrian Army was defeated tactically in the first engagements, it escaped and the French 2nd Grand Army [the 1st sent to campaign in Spain] was pursuing weakened Austrians to Vienna when the final defection of Napoleonic German client states in July had the French Army retreat with skirmishes and minor battles that decreased the Frenchmen. By September, the Rhine was reached and crossed, bringing Napoleon's Spanish Campaign to a close as the army, hampered by guerrillas, fought slowly with supplies overtaking production of military equipment.
By 18 October, the Rhine was crossed and the 2nd French Army was encircled, surrendering in 2 weeks. The last large offensive campaign of the year was to invade Holland and Belgium. During the year's end, Napoleon defeated another Prussian Army, but a combined Spanish-British Army with guerrillas would enter France from the south again and this time, the threat to the mountains were real that Napoleon couldn't exploit his last victories at Paris during the end of 1813 effectively. Over 20 to 26 December 1813, Napoleon defeated the Prussian Army one last time and captured many soldiers, but retreated to Paris just as the Coalition's Pyrenees crossing proved successful with Bordeaux threatened.
On 11 April 1814, the French defence of its Atlantic coast was lost when diversionary amphibious assaults and a landing in Normandy coordinated with an invasion from recently captured Toulouse combined to cut the French Atlantic coast from the rest of France. After 2 months of mopping up, Napoleon was defeated when the coalition forces met at a besieged Paris on 15 June. On 18 June, Napoleon's last breakout attempt to reach Paris saw his defeat and France surrendered 2 days later. What to do with Russia, Denmark-Norway, America and Portugal would be a part of a peace treaty, the other allies of Napoleon having surrendered without significant issues.