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The War of the Fourth Coalition

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The Road to the War

Napoleon smashed the combined armies of Austria and Russia at the Battle of Austerlitz in early December 1805. The decisive defeat of the allies forced Emperor Francis of Austria to make peace with Napoleon, while Tsar Alexander had no choice but to retreat home. Prussia was on the verge of entering the war on the side of the allies when news of Austerlitz reached the Prussian court. For the time being hostilities between France and Prussia were averted, but lingering resentment was already present between the two countries, which only grew during 1806. Napoleon used his stunning victory over the Third Coalition to reshape the face of the Old Continent. In early 1806 his subordinates deposed the Bourbon rulers of Naples. Napoleon placed his brother Joseph on the vacant throne, while he named another of his brother the king of the Netherlands. Napoleon reshaped Germany also. He created a French puppet buffer state, the Confederation of the Rhine, and elevated two of his allies, Bavaria and Wurtenberg to kingship.

Napoleon’s meddling in German affairs angered and humiliated both Austria and Prussia. Emperor Francis of the Holy Roman Empire finally dissolved the Empire of Charlemagne and took up the title of Emperor of Austria.

Napoleon tried to placate Prussia by offering them Hannover in exchange for some minor concessions to Napoleon’s rivals, but when the Prussian court received news that Napoleon offered Hannover back to Britain, they were both insulted and outraged by the duplicity of the French Emperor.

As the months of 1806 passed, the War Party of the Prussian court, led by the popular and charismatic queen Louise pushed the more cautious King into sending France an ultimatum, which ultimately led to the outbreak of the War of the Fourth Coalition.


For each question, choose the best answer. The answer key is below.

  1. Napoleon became emperor of France in?
    • 1803
    • 1804
    • 1805

Answer Key

  1. 1804

Napoleon Destroys Prussia

Much to the surprise of Napoleon, the Prussian High Command acted with incredible incompetence during the early phase of their confrontation. Such was the reckless incompetence of the Prussians that Napoleon, a man who was always preparing for a worst-case scenario, was often unable to make any sense of the intelligence he received.

The Prussian's gravest error was taking the fight against Napoleon only with the help of Saxony. The Russian and Swedish allies of the Prussians were still far away, while Napoleon’s army at the moment the war broke out was still stationed in south-central Germany. At first, Napoleon could not believe that the Prussians were reckless enough to fight him alone, and could not make sense of why they were not waiting for their allies.

The fog of war made predicting enemy movements very difficult. Napoleon correctly guessed that his enemies were concentrating their forces north of the Thuringian Forest. What Napoleon’s scouts got wrong was the exact location of the Prussians, as instead of Gera, the Prussians were assembling at the more western Erfurt.

The speed with which Napoleon’s army appeared in front of them shocked the Prussians, who decided to retread and march to Saxony. Marshall Lannes faced a Prussian force at the Battle of Saalfeld, and even a member of the Prussian Royal Family lost his life during the encounter. After receiving news from Lannes, Napoleon deduced that the Prussian main army was close to Lannes and ordered his forces to concentrate in the region around Jena.

In reality, the force Lannes detected at Jena was the Prussian rearguard, while the main army was further north at Auerstedt.

Josef Grassi: Portrait of Louise of Mecklenburg-Strelitz, Queen of Prussia

Josef Grassi: Portrait of Louise of Mecklenburg-Strelitz, Queen of Prussia

Napoleon instructed two of his marshalls, Davout and Bernadotte, to march north of Jena and fall on the northern flank and back of the Prussian army at Jena. Unfortunately for Davout, it meant that he marched straight into the Prussian main army.

The French overwhelmed the Prussians at Jena in a fiercely fought battle. The main Prussian army and Davout marched into one another, and another battle began. The French under Davout were outnumbered 2-1, luckily for him, his troops were battle-hardened and the Prussians failed to utilise their numbers. During the battle, the commander of the Prussian army, the Duke of Brunswick, was killed, which left King Frederick William in command. The King was not a good general, and his hesitancy allowed Davout to counterattack and rout the larger Prussian army.

After he received news of Davout’s victory, Napoleon at first had a hard time to even believing it, but once the news was confirmed, the emperor lauded the heroic marshal and his soldiers. Later he named him the Duke of Auerstedt.

Marshall Bernadotte on the other hand, was nearly court-martialled for his failure to reinforce Davout.

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In the aftermath of the twin battles of Jena-Auerstedt, the French relentlessly pursued the Prussians and did not give them time to regroup. Despite the fierce reputation of the Prussian army, all it took was one serious defeat, and the army disintegrated. Two weeks after the battles, the French army captured Berlin and paraded through the streets. The Prussian army more or less ceased to exist, as they lost 160,000 men killed, wounded and mostly captured in not much more than a month.

The King and the court fled to Konigsberg in East Prussia, banking on the Russians to defeat Napoleon for him and save his kingdom.

Russia enters the fray

The armies of Prussia collapsed in October 1806. A rump force remained under the command of the king in Eastern Prussia. Napoleon moved east to face these forces and the Russians.

By December, Napoleon was in Warsaw, but his efforts to win a quick victory over his remaining enemies were made impossible by the harsh climate and landscape of East Prussia. The freezing conditions and sea of mud forced Napoleon to send his troops into winter quarters. While searching for better quarters for his troops, Marshall Ney accidentally bumped into a surprise Russian advance.

After receiving news of this development, Napoleon ordered Ney and the rest of the French troops in the area to retreat and lure General Bennigsen West, while he and the rest of the army march to the back of the Russians. Luckily for Bennigsen, his scouts captured a French messenger carrying the orders of the emperor. Bennigsen just had enough time to escape encirclement and foil the trap of Napoleon.

The two armies finally met at the Battle of Eylau. In one of the bloodiest and most gruesome engagements of the war, the two sides fought each other to a draw. In what was the first battle where Napoleon failed to achieve a decisive victory since becoming emperor, both the Russians and the French may have lost as many as 20,000 men killed or wounded.

Antoine-Jean Gros: Napoleon on the Battlefield of Eylau

Antoine-Jean Gros: Napoleon on the Battlefield of Eylau

After the carnage of Eylau, both sides disengaged, and a lull in the fighting allowed them to reorganise their armies. Napoleon ordered new uniforms, supplies and reinforcements. By the time the fighting was restarted, Napoleon had 190,000 men under his command, while the combined Russo-Prussian army numbered only 115,000.

A newly formed corps besieged and captured the still Prussian occupied Danzig, a move that secured Napoleon’s northern flank.

Bennigsen once again took the initiative, but Marshall Ney was equal to his challenge and averted disaster. Once his element of surprise was gone, Bennigsen retreated once again. The French caught up with him at the Battle of Heislberg. Under the Command of Marshall Lannes and Murat, the French were repelled by the Russians. Despite causing significant casualties to their enemies, Bennigsen once again chose to retreat.

Bennigsen chose to retreat on the East side of the river Alle, while the French remained on the Western side of the river and marched towards Konigsberg. Three days later, Bennigsen came into contact with the corps of Marshall Lannes and decided to engage and destroy it.

To achieve this, Bennigsen had to cross the river. Unaware of the proximity of the rest of the French army, Bennigsen was marching right into a disaster. He believed he had more than enough time to destroy Lannes and cross to the other side of the river, but he was very mistaken.

He engaged Lannes with the vanguard of his crossing troops, but by the end of the day, Lannes’s force was still intact. Lannes also sent word to Napoleon to march to his aide, and by the next day, French troops were already arriving in great number. By the time the Battle of Friedland began on July 14, 1807, the French outnumbered the Russians, who were fighting with their back to the rives, and their troops were cut in half by a stream between their southern and northern troops.

The result of the battle was a decisive French victory. Bennigsen may have lost between 20,000-40,000 men killed, wounded, captured or missing, a devastating blow to his already outnumbered army.


The Campaigns of Napoleon by David Chandler


He retreated to Russia with his shaken army. The advisors of the Tsar convinced Alexander to make peace with Napoleon, and the two emperors met each other not much later.

At the Conference of Tilsit, the new order of the Continent was decided. Russia agreed to join France and even implemented Napoleon’s Continental System. Napoleon was lenient towards Alexander and only made him concede the Ionian Islands.

Prussia, on the other hand, got a much worse deal. Some of the Western regions of Prussia were reorganized into the Kingdom of Westphalia, ruled by Napoleon’s brother Jerome. Prussia also lost territories in the East, from which Napoleon formed the Grand Duchy of Warsaw, a French puppet Polish state.

This content reflects the personal opinions of the author. It is accurate and true to the best of the author’s knowledge and should not be substituted for impartial fact or advice in legal, political, or personal matters.

© 2022 Andrew Szekler

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