Why Was Napoleon Able to Conquer Europe?
The reasons behind the French conquest
I. The Grande Armée
Throughout his two-decade-long military career, Napoleon Bonaparte commanded his troops in sixty battles—winning over fifty, with only a handful of defeats. And even those defeats mostly came in the later years, when the French army was already badly depleted from the disastrous Russian campaign, often leaving Napoleon outnumbered and stretched thin.
Napoleon’s own brilliance played no small part in this stellar military record, but it own was only part of the equation.
To understand why Napoleon’s military machine became the most feared force in Europe, we need to travel back in time a bit.
With the introduction of gunpowder and the return of the pike to European warfare, the battlefield changed forever. Unlike knights and elite warriors of the past, wielders of these weapons were easy to train and deploy. Suddenly, rulers could raise vast armies, drawing from a much larger pool of soldiers than ever before.
By the 16th century, the size of European armies began to skyrocket. But there was a catch—most of these forces were only assembled for war.
Take the Spanish Army of Flanders for example: during peacetime, it numbered fewer than 20,000 men, yet in times of war, it ballooned to over 70,000.
Why? Money.
Even as monarchs began to extract more wealth from their kingdoms, they still couldn’t afford to keep large standing armies year-round.
Yet, as the 1600s progressed, Europe’s crowned heads and their ministers grew better at exploiting the resources of their kingdoms, allowing them to maintain larger permanent armies.
Leading the way was France under Louis XIV, followed by Austria, Russia, and Prussia—turning these four into the dominant powers of the continent.
And those who failed to adapt? Woe fell onto them.
The once-feared Ottoman Empire—a giant on Europe’s doorstep—fell behind in military innovation. By 1700, Austria had driven them out of Hungary. The Polish-Lithuanian Commonwealth fared even worse, vanishing from the map entirely as its neighbors carved it up.
But even as European armies became larger and more professional, they had glaring weaknesses…
For one, morale was an issue. Though social mobility though military service was possible, the chance to raise through the ranks was still quite slim, leaving a military career unattractive to the majority of commoners. As a result, European rulers relied on mercenaries and conscripts—men who had little loyalty to their cause and often deserted at the first opportunity.
Another major weakness of ancient regime armies was mobility. Or better said, a lack of mobility.
Most armies relied on supply depots scattered across strategic locations. If they strayed too far, they had to depend on slow-moving wagon convoys for food, fodder, and ammunition—grinding their movement to a halt.
And then there was leadership. While military academies were spreading, many high-ranking officers owed their positions to birth, not skill. Most generals were also quite cautious, avoiding large, costly battles in favor of sieges. Wars became wars of attrition rather than decisive conflicts.
By the end of the Seven Years’ War, the flaws of the old system were obvious. And in France, a country humiliated by its military failures during the Seven Year’s War, voices for reform grew louder.
Military thinkers like Guibert, Bourcet, and Gribeauval called for sweeping changes. Under the supervision of Gribeauval the French artillery was revolutionized, making it lighter, deadlier, and more mobile. But the biggest transformation came not from careful planning—but from chaos.
With the French Revolution rapidly radicalizing, the old aristocratic officer corps of the royal army fled en masse. Some estimates suggest half of France’s noble officers abandoned their posts.
At the same time, the levee en masse—mass conscription—swelled the army’s ranks in the mid 1790s. With the army greatly expanded and so many officers gone, the only solution was promotion by merit. This meant that compared to other European armies, in the French Revolutionary army an almost unheard of meritocracy became possible during the war of the first coalition.
This was how an entire generation of gifted commanders—Jean Lannes, Joachim Murat, Michel Ney—and most of all, Napoleon Bonaparte—came to power.
But the revolution didn’t just change leadership. It also forced the French military to rethink how it moved and fought.
Lacking a proper supply network to feed its greatly enlarged army, French armies had no choice but to live off the land. This often left them undersupplied, but it also made them faster than their enemies.
By the time Napoleon took power in 1800, all the ingredients for his war machine were in place. But it was his genius that took them to the next level.
His greatest creation? The Corps d’Armée system.
Instead of marching as one massive force, Napoleon divided his army into self-sufficient corps, each numbering between 15,000 and 30,000 men.
Each corps was strong enough to hold its own in battle, but small enough to move quickly and live off the land. They would march separately—but always within a day or two of each other.
If one corps encountered enemy resistance, nearby corps could rush to the fight, overwhelming the enemy before they could react.
This combination of speed, flexibility, and coordination was unlike anything Europe had seen before. It allowed Napoleon to outmaneuver his enemies—sometimes literally running circles around them.
II. Haphazard anti-French Coalitions and Napoleon’s Own Allies
With the Grande Armée, Napoleon commanded a force no single European power could face alone—least of all Britain, his most relentless enemy. Britain’s mighty navy made invasion impossible, but her small standing army meant that if Napoleon was to be defeated, it wouldn’t be British troops doing the job. Instead, Britain had to bankroll continental coalitions, enlisting Europe’s great powers—Austria, Prussia, and Russia—to take on Napoleon.
In theory, these nations had plenty of reasons to oppose France. The rapid French expansion into Italy and Germany came at the expense of both Austria and Prussia, while the revolutionary ideals that Napoleon embodied sent chills down the spine of Russia’s Tsar. Yet, while these powers all had their grievances, actually coordinating them into an effective coalition proved disastrous time and time again.
During the Wars of the Second, Third, and Fourth Coalitions, Britain never succeeded in uniting all three powers against Napoleon at the same time. In 1799-1800, Austria and Russia stood together, but Prussia remained neutral. In 1805, Austria and Russia once again fought Napoleon, while Prussia hesitated—only to begin mobilizing just as Napoleon’s stunning victory at Austerlitz shattered the coalition entirely. In 1806, Prussia finally joined the fight, but too late—Napoleon crushed them at Jena-Auerstedt before the Russians could arrive in force.
Even when coalitions did come together, their armies were rarely in sync. In 1800, Tsar Paul of Russia suddenly withdrew his troops after falling out with Austria. In 1805, by the time Russian forces even reached central Europe, Austria’s army on the Rhine had already been annihilated at Ulm. Time and again, these delays allowed Napoleon to defeat his enemies one by one, never having to face their full strength at once.
Napoleon’s Alliances: The Germans, Italians, and Poles
Had the Allies been able to coordinate better, their superior numbers could have compensated for their inferior leadership—but their failure to do so sealed their fate. Meanwhile, Napoleon wasn’t just winning battles; he was winning allies. In Germany, Italy, and Poland, he cultivated supporters, either installing loyal regimes or winning over existing ones, ensuring that when war came, France wasn’t fighting alone.
One of Napoleon’s most significant diplomatic successes was the creation of the Confederation of the Rhine in 1806. The Holy Roman Empire had been a loose, fragmented entity for centuries, and Napoleon shattered what remained of it after his victory at Austerlitz. In its place, he established a coalition of German client states, led by Bavaria, Saxony, and Württemberg. These states had long been overshadowed by Austria and Prussia—Napoleon’s promise of protection and territorial expansion made him a more attractive patron than the old order.
In return for their loyalty, these German states contributed tens of thousands of troops to Napoleon’s campaigns. By 1809, Napoleon’s German allies provided over 100,000 men, and by the Russian campaign of 1812, the Confederation of the Rhine supplied at least 120,000 troops—roughly a fifth of Napoleon’s total invasion force.
Napoleon’s control over Italy was even more direct. Having first conquered northern Italy in the late 1790s, he dismantled the old aristocratic regimes and replaced them with French-backed republics and kingdoms. The Kingdom of Italy, with Napoleon himself as its ruler, became a key satellite state, supplying both money and manpower to the French war effort.
By 1812, Italian forces fighting for Napoleon numbered around 50,000 troops, many of whom fought in Russia and later in the desperate campaigns of 1813-1814. The Neapolitan Kingdom, ruled by Napoleon’s brother-in-law Joachim Murat, also contributed forces, though Murat would later betray Napoleon when the empire began to crumble.
For many Italians, Napoleon’s rule brought modernization and reform, including new legal codes, infrastructure improvements, and greater social mobility. While not all welcomed French domination, for some Italians, Napoleon represented progress compared to the reactionary monarchies that had ruled before.
Perhaps Napoleon’s most fervent supporters came from Poland. The Polish-Lithuanian Commonwealth had been partitioned out of existence by Austria, Prussia, and Russia in the late 18th century, leaving Poles longing for a chance to restore their nation. Napoleon offered them exactly that.
After his defeat of Prussia in 1806, Napoleon created the Duchy of Warsaw, a Polish client state that gave Poles hope for full independence. In return, Polish forces eagerly took up arms for Napoleon, forming some of his most loyal and disciplined troops.
By 1812, Napoleon’s Polish allies provided around 98,000 soldiers, including the legendary Polish Lancers and cavalrymen who fought in nearly every major battle of the Napoleonic Wars. Polish troops played a critical role in the invasion of Russia, and even after Napoleon’s empire began to collapse, many Poles fought on, hoping he could still secure their freedom.
When it reached its peak, Napoleon’s empire wasn’t built on French bayonets alone. By securing the loyalty or submission of Germany, Italy, and Poland, he transformed France’s war effort into something much larger. The armies marching under his banner were a multinational force, drawing upon the manpower of conquered and allied nations.
While Britain financed Napoleon’s enemies, Napoleon forged alliances through conquest and reform, building a coalition of his own that would allow him to reshape Europe—for a time.
III. Napoleon’s Own Genius
The previous factors all played a role in Napoleon’s success, but it would be unfair to downplay the Emperor’s own talent for command. His record speaks for itself—his win ratio was higher than any other French commander of the era, and that was no accident.
During his prime, Napoleon was a workaholic par excellence, often working 16 to 18 hours a day, absorbing intelligence reports like a machine and formulating countermeasures at lightning speed. He could process vast amounts of information and exploit enemy weaknesses in ways his opponents simply could not. And nowhere was this ability more brilliantly displayed during the War of the Third Coaliton and especially at the Battle of Austerlitz, his greatest victory.
In 1805, when the Third Coalition formed against him, Napoleon was in northern France preparing for a potential invasion of Britain.
Due to the dominance of the British Royal Navy, an actual invasion was already a rather remote possibility only, but British Prime Minister William Pitt wasn’t willing to wait and he was adamant to crush French landpower also. To this end, he rallied Austria, Russia, Sweden, and Naples to form a new anti-French coalition and launch a massive four-pronged assault against France and her allies.
The plan was ambitious. While smaller forces struck in Italy and Germany, Austria’s Archduke Charles would invade Lombardy with 90,000 men, and the main allied army—an Austro-Russian force—would cross the Rhine and push into France itself.
But Napoleon wasn’t about to sit back and react. He moved first and turned the coalitions strategy against itself.
Rather than spread his forces thin to defend everywhere, he focused his strength where it mattered most—the Rhine. He struck into Germany before the Russians could even arrive, forcing General Mack and his 60,000-strong army to surrender at Ulm.
It was a devastating blow for the allies, but the war was far from over just yet.
Despite French attempts to destroy his force, General Kutuzov was able to escape his pursuers and linked up with other Russian and Austrian forces to form a strong, roughly 80,000 strong coalition force.
In Lombardy, Archduke Charles initially waged a cautious campaign against Marshall Massena, but once he learned of Mack’s demise, the archduke began to retreat towards Vienna. Though he was unable to save the capital, Charles succeeded to link up with the army of his brother to form a second, formidable coalition army.
While the allies now had two strong field armies, Napoleon’s strategic situation was deteriorating rapidly. Though the French captured Vienna in November, as they advanced further into the Austrian Empire, the supply lines of Napoleon’s army grew to enormous length, forcing him to diver a significant portion of his army to guard his supply lines and flanks, reducing his field army drastically.
Napoleon needed to force a battle—and fast. But how do you lure an enemy into fighting on your terms?
You make them believe they’ve already won.
Napoleon feigned weakness. He opened negotiations, acted hesitant before enemy envoys, and deliberately pulled his troops back from the Pratzen Heights—a key position on the battlefield. His goal? To convince the allies that he was vulnerable, that this was their moment to strike and finish him off.
The deception worked.
Tsar Alexander of Russia, eager for glory, overruled cautious voices like General Kutuzov and Emperor Francis of Austria and ordered an all-out attack, believing Napoleon was on the ropes.
But in reality, the Alexander was walking straight into a trap.
The Perfect Battle
Though Napoleon was confident his army had the measure of the allies in any condition, a simply victory was not enough. At Austerlitz he needed to crush his enemies, and inflict on them a defeat that was sobering enough to convince the allies to end the war immediately.
To achieve it, Napoleon came up with another deception, by ordering his troops to retreat from the Pratzen Heights, than leaving one of his flanks deliberately weakened, hoping these moves will lure the allies to launch an all out attack against his weakened flank.
The plan worked out to a treat, and the allies proceeded just as Napoleon expected. The allied attack against the weakened French flag left their own centre weakened in turn, presenting Napoleon the chance to launch his own attack and first cut the allied army in half, the swing back and capture a significant portion of the allied forces attacking his southern flank.
By the time the Battle of Austerlitz was over, Napoleon had his decisive victory and the allied army was scattered.
A demoralized Emperor Francis met Napoleon the following day and agreed to open negotiations for a treaty to end the war.
The War of the Third Coalition was Napoleon at his absolute peak, with the French Emperor showing his genius both on a strategic and tactical level, outwitting his enemies at every turn to turn several disadvantegous situations into an outright victory.
Emperor Francis of Austria was so shaken that he met Napoleon the very next day to negotiate peace. The war was over.
Austerlitz wasn’t just a victory—it was a masterpiece. Napoleon had outmaneuvered, outthought, and outclassed his enemies at every stage.
It was the perfect display of what made him such a fearsome force:
Strategic brilliance—striking first, forcing the enemy into bad decisions.
Deception—luring his opponents into a battle they thought they could win.
Tactical genius—delivering the decisive blow at the perfect moment.
At Austerlitz, Napoleon wasn’t just a great general—he was at the height of his power, it was the kind of victory that shaped the course of history.
Yet, in his greatest triumph, were already visible the potential seeds of defeat that signaled that even the brightest stars eventually fade.
Sources:
Chandler, David (1966). The Campaigns of Napoleon.
Elting, John R. (1988) Swords Around a Throne: Napoleon's Grand Armée.