1805 battle of the Napoleonic Wars
 War of the Third Coalition:Austria
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The Battle of Austerlitz (2 December 1805/11 Frimaire An XIV FRC), also known as the Battle of the Three Emperors, was one of the most important military engagements of the Napoleonic Wars. The battle occurred near the town of Austerlitz in the Austrian Empire (now Slavkov u Brna in the Czech Republic). Around 158,000 troops were involved, of which around 24,000 were killed or wounded. 
The battle is often cited by military historians as one of Napoleon's tactical masterpieces, in the same league as other historic engagements like Cannae or Gaugamela. The military victory of Napoleon's at Austerlitz brought the War of the Third Coalition to an end, with the Peace of Pressburg signed by the French and Austrians later in the month. These achievements did not establish a lasting peace on the continent. Austerlitz had driven neither Russia nor Britain, whose armies protected Sicily from a French invasion, to settle. Prussian resistance to France's growing military power in Central Europe led to the War of the Fourth Coalition in 1806.
After eliminating an Austrian army during the Ulm campaign, French forces seized Vienna in November 1805. The Austrians avoided further conflict until the arrival of the Russians, who helped increase the allied numbers. Napoleon sent his army north in pursuit of the Allies but then ordered his forces to retreat so he could feign a grave weakness to lure the Allies into thinking that they were facing a weak army, while it was in fact formidable. Napoleon gave every indication in the days preceding the engagement that the French army was in a pitiful state, even abandoning the dominant Pratzen Heights near Austerlitz. He deployed the French army below the Pratzen Heights and weakened his right flank, enticing the Allies to launch an assault there to roll up the French line. A forced march from Vienna by Marshal Davout and his III Corps plugged the gap left by Napoleon just in time. The Allied deployment against the French right weakened the Allied centre on the Pratzen Heights, which was attacked by the IV Corps of Marshal Soult. With the Allied center demolished, the French swept through both flanks and routed the Allies, which enabled the French to capture thousands of prisoners.
The Allied disaster significantly shook the will of Emperor Francis to further resist Napoleon. France and Austria agreed to an armistice immediately, and the Treaty of Pressburg followed shortly after, on 26 December. Pressburg took Austria out of both the war and the Coalition while reinforcing the earlier treaties of Campo Formio and of Lunéville between the two powers. The treaty confirmed the Austrian loss of lands in Italy and Bavaria to France, and in Germany to Napoleon's German allies. It also imposed an indemnity of 40 million francs on the Habsburgs and allowed the fleeing Russian troops free passage through hostile territories and back to their home soil. Critically, victory at Austerlitz permitted the creation of the Confederation of the Rhine, a collection of German states intended as a buffer zone between France and the eastern powers, Austria, Prussia and Russia. The Confederation rendered the Holy Roman Empire virtually useless, so Francis dissolved the Holy Roman Empire in 1806, but remained as emperor of Austria. These achievements failed to establish a lasting peace on the continent. Prussian worries about the growing French influence in Central Europe led to the War of the Fourth Coalition in 1806.
Background.
Europe had been in turmoil since the start of the French Revolutionary Wars in 1792. In 1797, after five years of war, the French Republic subdued the First Coalition, an alliance of Austria, Prussia, Great Britain, Spain, and various Italian states. A Second Coalition, led by Britain, Austria and Russia, and including the Ottoman Empire, Portugal and the Kingdom of Naples, was formed in 1798, but by 1801, this too had been defeated, leaving the British the only opponent of the new French Consulate. In March 1802, France and Britain agreed to end hostilities under the Treaty of Amiens.
However, many problems persisted between the two sides, making implementation of the treaty increasingly difficult. The British government resented having to return the Cape Colony and most of the Dutch West Indies to the Batavian Republic. Napoleon was angry that the British refused to abandon the island of Malta. The tense situation only worsened when Napoleon sent an expeditionary force to restore French authority and slavery in Saint-Domingue. In May 1803, Britain declared war on France.
Third Coalition.
In December 1804, an Anglo-Swedish agreement led to the creation of the Third Coalition. British Prime Minister William Pitt the Younger spent 1804 and 1805 in a flurry of diplomatic activity geared towards forming a new coalition against France, and by April 1805, Britain and Russia had signed an alliance. Having been defeated twice in recent memory by France and being keen on revenge, Austria joined the Coalition a few months later.
Forces.
French Imperial army.
Before the formation of the Third Coalition, Napoleon had assembled an invasion force called the "Armée d'Angleterre" (Army of England) around six camps at Boulogne in Northern France. He intended to use this force, amounting to 150,000 men, to strike at England and was so confident of success that he had commemorative medals struck to celebrate the conquest of the English. Although they never invaded, Napoleon's troops received careful and invaluable training for any possible military operation. Boredom among the troops occasionally set in, but Napoleon paid many visits and conducted lavish parades to boost morale.
The men at Boulogne formed the core for what Napoleon would later call . The army was organized into seven corps, which were large field units that contained 36 to 40 cannons each and were capable of independent action until other corps could come to their aid. A single corps (adequately situated in a solid defensive position) could survive at least a day without support. In addition to these forces, Napoleon created a cavalry reserve of 22,000 organized into two cuirassier divisions, four mounted dragoon divisions, one division of dismounted dragoons and one of light cavalry, all supported by 24 artillery pieces. By 1805, the had grown to a force of 350,000 men, who were well equipped, well trained, and led by competent officers.
Russian Imperial army.
The Russian army in 1805 had many characteristics of Ancien Régime organization. There was no permanent formation above the regimental level, and senior officers mostly belonged to aristocratic circles. The Russian infantry was considered one of the hardiest in Europe, with fine artillery crewed by experienced professional soldiers.
Austrian Imperial army.
Archduke Charles, brother of the Austrian Emperor, had started to reform the Austrian army in 1801 by taking away power from the , the military-political council responsible for the armed forces. Charles was Austria's most able field commander, but he was unpopular at court and lost much influence when, against his advice, Austria decided to go to war with France. Karl Mack became the new main commander in Austria's army, instituting reforms on the eve of the war that called for a regiment to be composed of four battalions of four companies, rather than three battalions of six companies.
Preliminary moves.
In August 1805, Napoleon, Emperor of the French since December of the previous year, turned his sights from the English Channel to the Rhine to deal with the new Austrian and Russian threats. On 25 September after a feverish march in great secrecy, 200,000 French troops began to cross the Rhine on a front of . Mack had gathered the greater part of the Austrian army at the fortress of Ulm in Swabia.
Napoleon swung his forces southward in a wheeling movement that put the French at the Austrian rear while launching cavalry attacks through the Black Forest, which kept the Austrians at bay. The Ulm Maneuver was well-executed, and on 20 October, 23,000 Austrian troops surrendered at Ulm, bringing the number of Austrian prisoners of the campaign to 60,000. Although this spectacular victory was soured by the defeat of a Franco-Spanish fleet at Trafalgar the following day, French success on land continued as Vienna fell in November. The French gained 100,000 muskets, 500 cannons, and intact bridges across the Danube.
Russian delays prevented them from saving the Austrian armies; the Russians withdrew to the northeast to await reinforcements and link up with surviving Austrian units. Tsar Alexander I appointed general Mikhail Illarionovich Kutuzov commander-in-chief of the combined Russo-Austrian force. On 9 September 1805, Kutuzov arrived at the battlefield, quickly contacting Francis I of Austria and his courtiers to discuss strategy and logistics. Under pressure from Kutuzov, the Austrians agreed to supply munitions and weapons promptly. Kutuzov also spotted shortcomings in the Austrian defense plan, which he called "very dogmatic". He objected to the Austrian annexation of the land recently under Napoleon's control because this would make the local people distrust the allied force.
The French followed after Kutuzov but soon found themselves in a difficult position. Prussian intentions were unknown and could be hostile; the Russian and Austrian armies had converged, and French lines of communication were extremely long, requiring strong garrisons to keep them open. Napoleon realized that to capitalize on the success at Ulm, he had to force the Allies to battle and then defeat them.
On the Russian side, Kutuzov also realized Napoleon needed to do battle, so instead of clinging to the "suicidal" Austrian defense plan, Kutuzov decided to retreat. He ordered Pyotr Bagration to contain the French at Vienna with 600 soldiers. He instructed Bagration to accept Murat's ceasefire proposal so the Allied Army could have more time to retreat. It was later discovered that the proposal was false and had been used to launch a surprise attack on Vienna. Nonetheless, Bagration held off the French assault for a time by negotiating an armistice with Murat, thereby providing Kutuzov time to position himself with the Russian rearguard near Hollabrunn.
Murat initially refrained from an attack, believing the entire Russian army stood before him. Napoleon soon realized Murat's mistakes and ordered him to pursue quickly, but the allied army had already retreated to Olmütz. According to Kutuzov's plan, the Allies would retreat further to the Carpathian region and "at Galicia, I will bury the French."
Napoleon did not stay still. The French Emperor decided to set a psychological trap to lure the Allies out. Days before any fighting, Napoleon had been giving the impression that his army was weak and desired a negotiated peace. About 53,000 French troops—including Soult, Lannes, and Murat's forces—were assigned to take Austerlitz and the Olmütz road, occupying the enemy's attention. The Allied forces, numbering about 89,000, seemed far superior and would be tempted to attack the outnumbered French army. However, the Allies did not know that Bernadotte, Mortier and Davout were already within supporting distance and could be called in by forced marches -- Bernadotte from Iglau, and Mortier and Davout from Vienna -- which would raise the French number to 75,000 troops.
Napoleon's lure did not stop at that. On 25 November, General Savary was sent to the Allied headquarters at Olmütz to deliver Napoleon's message, expressing his desire to avoid a battle while secretly examining the Allied forces' situation. As expected, the overture was seen as a sign of weakness. When Francis I offered an armistice on the 27th, Napoleon accepted enthusiastically. On the same day, Napoleon ordered Soult to abandon both Austerlitz and the Pratzen Heights and, while doing so, to create an impression of chaos during the retreat that would induce the enemy to occupy the Heights.
The next day (28 November), the French Emperor requested a personal interview with Alexander I. He received a visit from the Tsar's most impetuous aide, Prince Peter Dolgorukov. The meeting was another part of the trap, as Napoleon intentionally expressed anxiety and hesitation to his opponents. Dolgorukov reported an additional indication of French weakness to the Tsar.
The plan was successful. Many Allied officers, including the Tsar's aides and the Austrian Chief of Staff Franz von Weyrother, strongly supported an immediate attack and appeared to sway Tsar Alexander. Kutuzov's plan to retreat further to the Carpathian region was rejected, and the Allied forces soon fell into Napoleon's trap.
Battle.
The battle began with the French army outnumbered. Napoleon had