Napoleon's Austrian Conquest: Did It Happen?

Napoleon Bonaparte's military campaigns against the Austrian Empire were a key part of the Napoleonic Wars. The Austrian War of 1809, also known as the War of the Fifth Coalition, was sparked by Austrian attempts to liberate neighbouring countries from French rule. On April 8, 1809, Austrian troops invaded Bavaria, a French client state, in what they proclaimed was a War of German Liberation. In response, Napoleon boasted, Austria wants to get slapped; she shall have it... If the Emperor Francis attempts any hostile move, he will soon have ceased to reign.

Two weeks after the invasion, Napoleon forced the Austrians to retreat back across the border. He then captured Vienna on May 13, but Emperor Francis I refused to sign a peace treaty. To bring the Austrians to the negotiating table, Napoleon launched an attack from Lobau Island, west of Vienna, on May 22. Despite being outnumbered almost two to one, the French pushed the Austrians out of the village of Essling, inflicting heavy losses. However, the Austrians cut loose a floating flour mill upstream, smashing Napoleon's pontoon bridges and cutting his troops off from reinforcements and supplies. Napoleon crossed the river to reassure his men, but in the ensuing battle, he lost his most valuable marshal, Jean Lannes, who died from his wounds nine days later.

Undeterred, Napoleon prepared for a second assault. After rebuilding the bridges, he moved his troops across the river under the cover of a heavy thunderstorm on the night of July 4. On July 5 and 6, Napoleon led 173,000 troops into battle against 155,000 Austrians—the largest army he ever commanded. The Battle of Wagram, as it came to be known, resulted in 32,500 French casualties and 37,146 Austrian casualties. Despite the heavy losses on both sides, Napoleon declared victory, writing to his wife, Josephine, The enemy is retreating in disorder, and all is going as well as possible... I am sunburned.

In October 1809, Francis I signed a peace treaty with Napoleon. The terms were highly favourable to the Emperor of the French—three million of Francis' subjects became subjects of Napoleon, and Austria was forced to cede territory. It was the fourth and final time the Austrians were defeated by Napoleon.

The Austrian War of 1809

The Austrian invasion was an attempt to recover territories lost in the War of the Third Coalition. The Austrians hoped that Prussia would support them, but they remained neutral. Napoleon arrived to take command on the 17th of April and led an advance to Landshut, hoping to cut off the Austrian line of retreat. The Austrians were able to cross the Danube at Regensburg, which allowed them to retreat eastwards. Napoleon's first attempt to cross the Danube was repulsed at the Battle of Aspern-Essling, but he was successful in July.

Napoleon won a major victory at the Battle of Wagram on the 5th and 6th of July, forcing the Austrians to sign the Armistice of Znaim on the 12th of July. The French suffered heavy losses, with around 32,000 casualties, and Napoleon's armies were increasingly composed of non-French contingents. However, the Austrian casualties were only slightly greater than those of the French and their allies, and the defeat shattered the morale of the Austrians. The Treaty of Schönbrunn was regarded as harsh towards Austria, as they lost their Mediterranean ports and 20% of their population.

Napoleon's Invasion of Vienna

In 1809, the French military presence in the Confederation of the Rhine was diminished as Napoleon transferred a number of soldiers to fight in the Peninsular War. As a result, the Austrian Empire saw its chance to recover some of its former sphere of influence and invaded the Kingdom of Bavaria, a French ally. Recovering from his initial surprise, Napoleon beat the Austrian forces and occupied Vienna at the beginning of May 1809. Despite the string of sharp defeats and the loss of the empire's capital, Archduke Charles salvaged an army, with which he retreated north of the Danube. This allowed the Austrians to continue the war. Towards the end of May, Napoleon resumed the offensive, suffering a surprise defeat at the Battle of Aspern-Essling.

Napoleon took more than six weeks to plan and prepare contingencies before making another attempt at crossing the Danube. He amassed a 172,000-man French, German and Italian army in the vicinity of Vienna. The Battle of Wagram began after Napoleon crossed the Danube with the bulk of these forces during the night of July 4 and attacked the 136,000-man strong Austrian army. Having successfully crossed the river, Napoleon attempted an early breakthrough and launched a series of evening attacks against the Austrian army. The Austrians were thinly spread in a wide semicircle, but held a naturally strong position. After the attackers enjoyed some initial success, the defenders regained the upper hand and the attacks failed. Bolstered by his success, the next day at dawn Archduke Charles launched a series of attacks along the entire battle line, seeking to take the opposing army in a double envelopment. The offensive failed against the French right but nearly broke Napoleon's left. However, the Emperor countered by launching a cavalry charge, which temporarily halted the Austrian advance. He then redeployed IV Corps to stabilise his left, while setting up a grand battery, which pounded the Austrian right and centre. The tide of battle turned and the Emperor launched an offensive along the entire line, while Maréchal Louis-Nicolas Davout drove an offensive, which turned the Austrian left, and rendered Charles's position untenable. Towards mid-afternoon on July 6, Charles admitted defeat and led a retreat, frustrating enemy attempts to pursue. After the battle, Charles remained in command of a cohesive force and decided to retreat to Bohemia. However, the Grande Armée eventually caught up with him and scored a victory at the Battle of Znaim. With the battle still raging, Charles decided to ask for an armistice, effectively ending the war.

The Battle of Aspern-Essling

The battle was fought near the Lobau floodplain, on the northern side of the Danube River in Lower Austria, in the villages of Aspern and Essling. Napoleon had around 24,000 men and 60 cannons, while the Austrian army, led by Archduke Charles, had 95,000 men and 200 cannons.

Napoleon had been directing his troops from Paris, but due to poor atmospheric conditions hindering telegraph transmissions, his orders were contradicted and confused. However, when he arrived on the scene on 17 April, he performed the successful "Landshut manoeuvre". Despite this, Napoleon was still unsure about Austrian planning and intentions. He chose to attack from Lobau Island, a risky move as the bridges were vulnerable to Austrian barges that could be set alight and floated downstream.

The battle began at 2:30 pm on 21 May. The Austrians attacked Aspern and the nearby woods, but their efforts were poorly coordinated and failed. Later assaults succeeded in taking and holding the western portion of the village. The French successfully repulsed the attacks against Essling throughout the day. Fighting resumed early on 22 May, and by dawn, Aspern was once again under French control. Napoleon then launched a massive assault against the Austrian centre, but the Austrians, inspired by the personal presence of Archduke Charles, opened heavy fire, causing the French to fall back. Napoleon received news that the bridge had broken again, preventing reinforcements from joining the battle. The French position became untenable, and Napoleon ordered a retreat to Lobau Island by nightfall.

The two-day battle was fierce and bloody, with huge losses on both sides. The French suffered between 20,000 and 23,000 casualties, including one of Napoleon's closest friends and ablest field commanders, Marshal Jean Lannes. The Austrian losses were comparable, with 19,000 killed and wounded, and 700 captured. The battle demonstrated that Napoleon could be defeated on the battlefield, and it damaged his aura of invincibility.

The Battle of Wagram

In 1809, the French military presence in the Confederation of the Rhine was reduced as Napoleon transferred soldiers to fight in the Peninsular War. The Austrian Empire saw this as an opportunity to recover its former sphere of influence and invaded the Kingdom of Bavaria, a French ally. Napoleon was initially surprised by the Austrian invasion but soon beat the Austrian forces and occupied Vienna at the beginning of May 1809. Despite the defeat and the loss of the empire's capital, Archduke Charles salvaged an army and retreated north of the Danube, allowing the Austrians to continue the war.

Napoleon resumed the offensive towards the end of May but suffered a surprise defeat at the Battle of Aspern-Essling. It took him six weeks to prepare his next offensive, during which he amassed a 172,000-man French, German, and Italian army in the vicinity of Vienna. The Battle of Wagram began after Napoleon crossed the Danube with the bulk of his forces during the night of 4 July and attacked the 136,000-man strong Austrian army.

The Austrian army was thinly spread in a wide semicircle but held a naturally strong position. Napoleon attempted an early breakthrough and launched a series of evening attacks. After some initial success, the Austrian defenders regained the upper hand and the attacks failed. The next day, at dawn, Archduke Charles launched a series of attacks along the entire battle line, seeking to take the opposing army in a double envelopment. The offensive failed against the French right but nearly broke Napoleon's left. Napoleon countered by launching a cavalry charge, which temporarily halted the Austrian advance. He then redeployed IV Corps to stabilise his left, while setting up a grand battery, which pounded the Austrian right and centre. Napoleon then launched an offensive along the entire line, while Maréchal Louis-Nicolas Davout drove an offensive, which turned the Austrian left, and rendered Charles's position untenable.

Mid-afternoon on 6 July, Charles admitted defeat and led a retreat, frustrating enemy attempts to pursue. The battle was particularly bloody, with 74,000 casualties, mainly due to the use of 800 artillery pieces and 200,000 rounds of artillery ammunition on a flat battlefield packed with some 300,000 men. The defeat shattered the morale of the Austrians, who could no longer find the will to continue the struggle. The Treaty of Schönbrunn followed, resulting in the loss of one-sixth of the Austrian Empire's subjects, along with some territories, rendering it landlocked until the German Campaign of 1813.

The Treaty of Schönbrunn

During the Peninsular War and the Spanish resistance against Napoleon, Austria had tried to reverse the 1805 Peace of Pressburg by sparking national uprisings in the French-occupied territories of Central Europe (most notably the Tyrolean Rebellion against Napoleon's Bavarian allies). These attempts ultimately failed, after French forces occupied Vienna in May 1809. The Austrians under Archduke Charles were able to repulse them at the Battle of Aspern on 21-22 May; however, Napoleon withdrew his forces and crushed Charles' army at Wagram a few weeks later. The archduke had to sign the Armistice of Znaim on 12 July. In October, Austrian Foreign Minister Johann Philipp Stadion was superseded by Klemens von Metternich.

The treaty imposed harsh peace terms: Austria had to cede the Duchy of Salzburg to Bavaria and lost its access to the Adriatic Sea by waiving the Littoral territories of Gorizia and Gradisca and the Imperial Free City of Trieste, together with Carniola, the March of Istria, western ("Upper") Carinthia with East Tyrol, and the Croatian lands southwest of the river Sava to the French Empire (see Illyrian Provinces). West Galicia was ceded to the Duchy of Warsaw, and Tarnopol district to the Russian Empire.

Austria recognized Napoleon's previous conquests from other nations as well as the rule of his brother Joseph Bonaparte as King of Spain. Austria also paid to France a large indemnity and the Austrian army was reduced to 150,000 men—a promise not fulfilled. The Graz Schlossberg fortress, whose garrison had firmly resisted the French occupation forces, was largely demolished.

Austria also had to apply Napoleon's Continental System, as Britain remained at war with France.

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