National opposition to France had strong social roots in Spain, more than anywhere else in Europe. As early as the sixteenth century, Spain had attained political union. The peasants of Spain were committed to the governing family and, in particular, to the Roman Catholic Church.

Since 1796, France and Spain had been allies. However, in 1807, a French army invaded the Iberian Peninsula, forcing Portugal to break its longstanding allegiance with Britain. The troops remained in Spain to secure supply and communication routes. Napoleon exploited an uprising in Madrid in 1808 as justification to remove the Spanish Bourbons and install his brother Joseph (1768–1844) on the Spanish throne. Attacks on ecclesiastical privileges heightened public indignation.

Napoleon encountered a new type of warfare in Spain.

Guerrilla groups cut communication lines, murdered stragglers, destroyed isolated troops, and then vanished into the mountains. To help the Spanish revolutionaries, the British landed a force led by Sir Arthur Wellesley (1769–1852), afterwards Duke of Wellington. Thus started the protracted peninsular campaign, which would drain French might from other parts of Europe and expedite Napoleon's collapse.

Because of the French issues in Spain, the Austrians decided to restart the war in 1809. They had sought vengeance since their humiliation at Austerlitz.

The Austrians anticipated Napoleon's diversion in Spain, French battle fatigue, and assistance from other German princes. However, Napoleon was firmly in authority in France, and the German princes did not move.

The naploenic wars wreaked havoc across Europe. Different participants, authors, and artists depicted the experience of combat in various ways. William Napier described his own heroism in a matter-of-fact tone.

Ernest Moritz Arndt, a German poet and historian, remembers periods of great patriotic fervor. Goya, a Spanish painter, depicted a time of immense brutality faced by the Spanish at the hands of French forces.

In 1807, Napoleon began sending soldiers into Spain when the King of Spain decided to join France against Portugal, which was aiding Britain. By early 1808, Spain had effectively become an occupied country. On May 2, riots erupted in Madrid between French troops, many of whom were Islamic soldiers recruited in Egypt by Napoleon, and Spanish residents.

In reaction to this resistance, the French commander Murat ordered the death of a large number of Madrid residents on the nights of May 2 and 3. The events of these two days signaled the start of Spain's campaign to free its peninsula from French domination.

Following the restoration of the Spanish monarchy, Francisco Goya (1745–1828) captured the heinousness of the killings in his painting

Napoleon was adamant about putting a stop to the Russian military menace. He built an army of about 600,000 troops, including a core of Frenchmen and over 400,000 warriors from the rest of his realm. He planned a quick campaign capped by a decisive fight, but the Russians fled before he could advance.

His overwhelming numerical superiority—the Russians only had roughly 160,000 troops—made it foolhardy for them to undertake a war. Instead, they used a "scorchedearth" strategy, burning all food and supplies as they fled. The so-called Grand Army of Napoleon could not survive on the land, and the vastness of Russia rendered supply lines impossible to sustain. Terrible rains, scorching heat, food and water shortages, and the bravery of the people.

Napoleon was adamant about putting a stop to the Russian military menace. He built an army of about 600,000 troops, including a core of Frenchmen and over 400,000 warriors from the rest of his realm. He expected to run the typical short campaign, culminating with a d Napoleon's aides encouraged him to abandon the campaign, but he was afraid that a failure would damage his authority in the empire and in France. He put his trust in the Russians' refusal to evacuate Moscow without a battle.

In September 1812, Russian popular sentiment compelled the army to give Napoleon the fight he desired, despite the willful Russian commander Mikhail Kutuzov's (1745–1813) desire to let the Russian winter crush the invader. The fiercest battle took place in Borodino, not far west of Moscow.

The deadliest fight of the Napoleonic period took place at Borodino, not far west of Moscow, and cost the French 30,000 fatalities and the Russians nearly twice that many. Nonetheless, the Russian army was not annihilated. Napoleon gained nothing significant from the war, and it was seen as a setback for him.

As winter approached in a large and hostile nation, fires ignited by the Russians quickly burned Moscow, leaving Napoleon far from home with a critically depleted army and little supplies. Following the capture of the burned-out city, Napoleon made multiple peace overtures to Alexander, but the tsar turned them down. By October, what remained of the Grand Army had been forced to flee. By December, Napoleon had concluded that the Russian disaster would incite domestic conspiracies against him.

He retreated to Paris, leaving the remainder of his army to fight their way west. Perhaps just 100,000 of the original 600,000 people survived. The winning alliance was held together by fear of Napoleon and resistance to his aims. As soon as he was ousted, the allies set about pursuing their own goals.

The British foreign secretary, Robert Stewart, Viscount Castlereagh (1769–1822), was instrumental in bringing them together. On March 9, 1814, even before the victorious army had entered Paris, he arranged for the Treaty of Chaumont to be signed.

It called for the return of the Bourbons to the French monarchy and the reduction of France to its 1792 borders. More crucially, the United Kingdom, Austria, Russia, and Prussia decided to join a Quadruple Alliance.

More crucially, Britain, Austria, Russia, and Prussia agreed to join a Quadruple Alliance for the next twenty years in order to protect whatever solution they reached. The remaining issues, and there were many, were left for a meeting to be convened in Vienna.

Tallyrand calmly watches which way the wind is blowing in this political cartoon of the Congress of Vienna, Castlereagh hesitates, and the rulers of Russia, Prussia, and Austria make the Holy Alliance dance. The king of Saxony retains his throne, while the republic of Geneva pays tribute to the kingdom of Sardinia.

The Congress of Vienna convened in September 1814, although its work was not completed until November 1815. Despite the presence of a glittering array of heads of state, the conference's primary work was carried out by the four great powers. The sole full session of Congress was held to confirm the agreements agreed by the big four. France was the easiest problem for the major countries to solve.

All of the victorious nations agreed that no single country should be permitted to rule Europe, and they were all resolved to keep France from doing so again. The temporary reinstatement of the French Bourbon monarchy, as well as a nonvindictive boundary solution, were intended to keep France quiet and content.

The powers also fortified the states surrounding France's frontiers in order to act as obstacles to fresh French expansion. In the north, they founded the kingdom of the Netherlands, which comprised Belgium and Luxembourg, and in the south, they added the vital port of Genoa to reinforce Piedmont.

To dissuade French expansion in the West, Prussia was handed vital additional holdings along the Rhine River.

Austria seized complete control of northern Italy in order to prevent a repeat of Napoleon's victories there. In terms of the rest of Germany, much of Napoleon's territorial arrangements were preserved. The old Holy Roman Empire, which had been disbanded in 1806, was not resurrected.