War of the Third Coalition
The War of the Third Coalition was a conflict that remade Europe in the space of a few months in 1805 and into 1806. At its heart was a single breathtaking military campaign that ended with Napoleon standing in Vienna, an Austrian army of tens of thousands laying down its arms, and two emperors watching their alliance shatter at a crossroads village in Moravia. How did France achieve so much so quickly? And why did the peace that followed unravel almost at once? Those are the questions this documentary sets out to answer.
The war grew from an unstable peace. The Treaty of Amiens in 1802 was supposed to end hostilities between France and Britain, but within months it was plain to nearly everyone that it would not hold. Napoleon was expanding his influence across Italy, keeping French troops in the Netherlands, and eyeing Egypt. Britain refused to give up Malta. By the 18th of May 1803, Britain declared war on France, and the countdown to a wider European conflict had begun.
The Treaty of Amiens rested on a set of conditions that Napoleon had no intention of honoring. France was to withdraw from the Netherlands, but instead Napoleon gave the Batavian Republic a new constitution modeled on French governance. Switzerland, officially independent, was bound politically to France for fifty years under the Act of Mediation. Napoleon annexed Piedmont outright and transformed the Cisalpine Republic into the Italian Republic, naming himself its president. French newspapers were even reporting that ten thousand men would be sufficient to reconquer Egypt.
Britain's obligations under Amiens were also conditional. The treaty required London to return conquered territories and hand Malta to the Order of St. John. But keeping France out of the eastern Mediterranean demanded that Britain hold Malta and maintain a fleet there. Napoleon pressed the point on the 13th of March 1803, confronting British ambassador Lord Whitworth over Britain's refusal to fully implement Amiens. Whitworth returned to London, and war followed within weeks.
For over two years after that declaration, Britain fought alone. Russia did not join a formal alliance until the 11th of April 1805. Austria signed onto the coalition on the 9th of August, and Naples-Sicily followed on the 11th of September. Sweden had entered earlier, in December 1804. Prussia chose to remain neutral throughout. The coalition was fragile by design: each member had its own priorities, and the dates of their formal commitments told a story of hesitation and calculation.
While diplomats were signing treaties, Napoleon was turning an invasion force into something Europe had never encountered before. He had assembled the Army of England in six camps around Boulogne in northern France, with the original intention of crossing the Channel. The men never set foot on British soil, but the training they received at Boulogne proved to be invaluable preparation for any military operation.
From this force Napoleon forged what he called La Grande Armee. At the outset it comprised roughly 200,000 men organized into seven corps, each structured to operate independently or in coordination with the others. A typical corps contained two to four infantry divisions, a cavalry division, and between 36 and 40 cannon. On top of this, Napoleon created a cavalry reserve of 22,000 men organized into cuirassier and dragoon divisions, supported by 24 artillery pieces. By 1805, the total force had grown to 350,000 men, well equipped and led by a skilled officer class.
The armies opposing France were organized along older principles. The Imperial Russian Army in 1805 had no permanent formations above the regimental level, and senior officers were drawn largely from aristocratic circles. Discipline relied on physical punishment, and many junior officers struggled to execute the complex manoeuvres that modern battle demanded. Austria's position was more complicated. Archduke Charles, brother of the Austrian Emperor and the army's best field commander, had begun reforming the Hofkriegsrat as early as 1801. But Charles was unpopular at court, and when Austria decided to go to war against his advice, General Karl Mack was given command instead. On the eve of war, Mack introduced sweeping changes to infantry regimental structure, requiring each regiment to field four battalions of four companies rather than three battalions of six. No corresponding officer training accompanied the change.
General Mack made his headquarters at Ulm, a city he considered virtually impregnable thanks to the heavily fortified Michelsberg heights. His defensive strategy called for holding the line until the Russian army under Mikhail Kutuzov could arrive and shift the balance. Mack believed the French would approach through the Black Forest, as they had in earlier Revolutionary Wars campaigns, and he prepared to seal those mountain passes.
Napoleon had studied the same terrain and reached the opposite conclusion. He sent Marshal Murat's cavalry sweeping across the Black Forest to maintain the illusion of a direct west-east advance, while 210,000 French troops from the Boulogne camps swung in a vast arc around Mack's northern flank. On the 27th of August 1805, only two days before this massive wheeling movement began, Napoleon had formally abandoned his invasion plans for England. His Boulogne force had found a new target.
The encirclement closed methodically. On the 8th of October, the first serious battle of the campaign took place at Wertingen, where Auffenburg's force of 5,000 infantry and 400 cavalry was caught by Murat's cavalry and Oudinot's grenadiers. The Austrians lost nearly their entire force, with between 1,000 and 2,000 taken prisoner. Fighting at Günzburg and Elchingen followed, and Ney earned the title Duke of Elchingen for his capture of the abbey at bayonet point on the heights above the town. By mid-October, Mack's army was sealed inside Ulm with no viable escape.
The Austrian command collapsed under the pressure. Archduke Ferdinand overrode Mack's objections and ordered the evacuation of all cavalry from the city, a total of 6,000 troopers. Murat's pursuit was so relentless that only eleven squadrons reached safety. Murat then forced General Werneck to surrender with 8,000 men at Trochtelfingten on the 19th of October, and swept on to capture another 12,000 Austrians near Neustadt. Inside Ulm, Napoleon's emissary Ségur signed a convention with Mack on the 17th of October: the Austrians would surrender on the 25th if no relief arrived. Mack capitulated five days early, on the 20th of October. On the 21st, the vast majority of the Austrian force laid down their arms with the Grande Armee drawn up in a semicircle to watch.
After Ulm, the main body of the Grande Armee pursued the retreating Austrians and the withdrawing Russian army under Kutuzov toward Vienna. Kutuzov fought skillful rearguard actions, including a costly trap at Dürenstein where General Gazan's division lost close to 40 percent of its strength, along with 47 officers, 895 men, and the eagles of the 4th Infantry Regiment and 4th Dragoons. On the 13th of November 1805, Marshals Murat and Lannes captured the bridge over the Danube at Vienna by falsely claiming an armistice was in effect, then rushing the bridge while the guards were distracted.
The two sides eventually gathered on the plains east of Brünn. Napoleon could field approximately 75,000 men and 157 guns for the battle, but roughly 7,000 troops under Davout were still far to the south. The Allies had around 73,000 soldiers, with seventy percent of them Russian, and 318 guns. On the 1st of December 1805, both sides took up their main positions. An aide recorded that Napoleon repeatedly told his marshals: "Gentlemen, examine this ground carefully, it is going to be a battlefield; you will have a part to play upon it."
Napoleon deliberately weakened his right flank to invite an Allied attack there. His plan called for 16,000 troops of Soult's IV Corps to drive through the centre and seize the Pratzen Heights once the Allies had stripped their centre bare. Davout's III Corps was ordered to force march 110 kilometres in 48 hours to support the exposed southern flank. Around 8:45 in the morning on the 2nd of December, Napoleon asked Soult how long it would take his men to reach the Pratzen Heights. Soult replied: "Less than twenty minutes, sire." Napoleon waited another fifteen minutes, then ordered the attack, saying: "One sharp blow and the war is over."
A dense morning fog covered the French advance. As Soult's men climbed the slope, the famous Sun of Austerlitz burned through the mist. Russian commanders on the heights were stunned to see the scale of the French assault. Bitter fighting swept across the Pratzen, through Sokolnitz, and along the northern flank where Lannes drove Bagration from the field. The climax came in the south, where St. Hilaire's division and part of Davout's corps shattered the Allied left. The Allied commander Buxhowden, completely drunk, fled the field. General panic seized the entire Allied force. Russian troops retreating via the Satschan frozen ponds were reportedly subjected to French artillery, though sources differ widely on casualties, with estimates ranging from 200 to 2,000 dead in that incident alone. Napoleon later exaggerated the episode in his official report, and some historians consider it largely a myth.
The campaign in Italy and Naples ran in parallel with the main operations in Central Europe, and its final chapter proved the most troubling for France. After the Battle of Caldiero between the 29th and the 31st of October 1805, Archduke Charles's Austrian army was forced into retreat. A Habsburg rear force of 4,400 men was defeated and captured by Jean Reynier and St. Cyr at Castelfranco Veneto on the 24th of November 1805.
When Austria signed the Treaty of Pressburg on the 26th of December, the Russians withdrew from Naples and the British evacuated the Italian mainland entirely, retreating to Sicily. French troops reorganized as the Army of Naples under the nominal command of Napoleon's brother Joseph Bonaparte, with the seasoned Marshal Masséna as the actual operational commander. On the 9th of February 1806, Masséna invaded the Kingdom of Naples. Two days later, King Ferdinand IV fled to Sicily under British naval protection. By the end of February, only the fortress city of Gaeta to the north of Naples and the region of Calabria in the south still held out.
Ferdinand had hoped to repeat the events of 1799, when a popular uprising in Calabria had toppled the French-backed Parthenopaean Republic. Initially no rebellion materialized, and on the 3rd of March General Reynier invaded Calabria with his 10,000-strong II Corps. The Royal Neapolitan Army was defeated at the Battle of Campo Tenese on the 10th of March 1806. The day after Campo Tenese, Joseph was installed as King of Naples.
Then the situation changed. Reynier's corps was forced to live off the land because of supply failures, and his seizures of provisions from local peasants who were already close to starvation triggered a revolt by the end of March. Small partisan bands grew into village-wide uprisings. The British dispatched an expeditionary force under Sir John Stuart, which won an early success at Maida, but London failed to reinforce Stuart or attempt to relieve the Siege of Gaeta. Gaeta surrendered on the 18th of July, freeing Masséna to march south and support Reynier. The revolt was not finally suppressed until 1807, by which time Masséna had already requested permission to relinquish command. For the first time in the Napoleonic Wars, France had experienced a sustained guerrilla campaign by a rebellious civilian population, and Reynier's use of terror tactics to suppress it was a preview of the far larger struggle Joseph Bonaparte would face in Spain during the Peninsular War.
The Treaty of Pressburg, signed on the 26th of December 1805, forced Austria to recognize French territorial gains from the earlier treaties of Campo Formio and Lunéville, to cede lands to Bavaria, Württemberg, and Baden, to pay an indemnity of 40 million francs, and to hand Venetia to the Kingdom of Italy. The Russian army was allowed to withdraw with its arms and equipment intact.
The war's political consequences extended far beyond Austria's losses. In July 1806, Napoleon created the Confederation of the Rhine, a collection of German client states pledged to raise an army of 63,000 men with Napoleon as their Protector. Membership required leaving the Holy Roman Empire. Emperor Francis II complied, abdicating the Imperial throne and becoming Francis I, Emperor of Austria. The Holy Roman Empire, which had existed in various forms for centuries, ceased to exist in 1806.
Austerlitz had driven neither Russia nor Britain out of the fight. Britain's Royal Navy had already demonstrated at Trafalgar in October 1805 that it commanded the seas. Sicily remained beyond French reach under British naval protection. And Prussia, which had watched the French annexation of Hanover and the creation of the Confederation of the Rhine with mounting alarm, went to war with France in 1806. The French losses in the 1805 Austrian campaign alone totalled 5,300 killed and 22,200 wounded, with total 1805 French casualties across all theatres reaching 12,000 killed and 22,200 wounded. Austria lost 20,000 killed and wounded and 70,000 as prisoners. Russia suffered 25,000 killed and wounded and another 25,000 captured. In 1808, Joachim Murat became the King of Naples after Joseph Bonaparte moved to Spain, and Murat's repeated attempts to cross the Strait of Messina and seize Sicily from British-protected Ferdinand all ended in failure.
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Common questions
When did the War of the Third Coalition start and end?
From the British perspective, the war began on the 18th of May 1803 when Britain declared war on France after the breakdown of the Peace of Amiens. The main phase of coalition fighting ended with the Treaty of Pressburg on the 26th of December 1805, though the subsequent French invasion of Naples continued into July 1806. Historians differ on whether the Naples campaign is part of the Third Coalition or not.
Who were the members of the Third Coalition against Napoleon?
The Third Coalition comprised the United Kingdom, the Austrian Empire, the Russian Empire, Naples, Sicily, and Sweden. Sweden entered into an alliance with Britain in December 1804, Russia formally joined on the 11th of April 1805, Austria on the 9th of August, and Naples-Sicily on the 11th of September. Prussia remained neutral throughout.
What happened at the Battle of Austerlitz?
On the 2nd of December 1805, Napoleon's forces defeated a combined Austro-Russian army east of Brünn in what became the decisive engagement of the war. Napoleon deliberately weakened his right flank to draw the Allied attack, then drove Soult's IV Corps through the Allied centre to seize the Pratzen Heights. The Allied army broke in a general panic, losing around 25,000 killed and wounded and 25,000 captured.
What were the terms of the Treaty of Pressburg after the War of the Third Coalition?
Signed on the 26th of December 1805, the Treaty of Pressburg required Austria to recognize French gains from the earlier treaties of Campo Formio and Lunéville, cede lands to Bavaria, Württemberg, and Baden, pay a war indemnity of 40 million francs, and surrender Venetia to the Kingdom of Italy. The Russian army was permitted to withdraw with its arms and equipment through hostile territory.
What was the Ulm Campaign in the War of the Third Coalition?
The Ulm Campaign ran from late September to the 20th of October 1805, when General Mack surrendered the bulk of the Austrian army encircled at Ulm. Napoleon feinted through the Black Forest while swinging 210,000 troops in a wide arc to trap Mack. The campaign ended with the Austrian force laying down its arms, with only around 10,000 troops escaping.
What was the significance of the Calabrian insurrection during the War of the Third Coalition?
The Calabrian insurrection of 1806 was the first sustained guerrilla war the French encountered in the Napoleonic Wars. After French supply failures led General Reynier to seize food from starving peasants, a popular revolt spread across Calabria that was not suppressed until 1807. The French response, relying on terror tactics, foreshadowed the far larger guerrilla conflict Joseph Bonaparte would face in Spain during the Peninsular War.
All sources
3 references cited across the entry
- 1journalThe Armies of EuropeFriedrich Engles — August 1855
- 3bookThe Napoleonic WarsGunther E. Rothenberg — Cassell — 1999