Why Napoleon’s Makeshift Army Ultimately Lost the Most Famous Battle in European History

Napoleon Bonaparte’s Waterloo army was the last he would ever lead into combat. Returning from exile in March 1815 to a country riven by factionalism and exhausted by two decades of almost unremitting warfare, the French emperor managed in only three months to pull together an army that came achingly close to defeating an allied force with almost double its numbers.

On paper, this army was formidable: veteran soldiers under experienced leaders, buoyed by enthusiasm for their returned emperor. Yet in reality, the force was pasted together: Veterans rubbed shoulders with volunteers, brilliant generals served alongside glorified bureaucrats, and regiments boasted hundreds of former prisoners of war, returning retirees, and men drafted at the last moment. An extemporized and makeshift force, it performed with enormous bravery, but in battle it would suffer from poor cohesion, coordination, and command and control, which, along with tactical errors and sheer weight of numbers, would ultimately cost it dearly on the field of Waterloo.

Raising an Army

The army that Napoleon inherited was far from ready for a major European war. Since his abdication a year before, it had been reduced to under 200,000 men. The much-vaunted Imperial Guard had been whittled down to two regiments, the cavalry had only 20,000 horses, and line regiments had been amalgamated, reorganized, and renumbered. Tens of thousands of veterans had been sent home, and thousands of officers were on half pay. Napoleon’s first task was to remobilize as much of this manpower as possible. On March 28 he recalled all former soldiers to the colors, hoping to raise over 100,000 fit men. His next task was to ensure the army’s loyalty by purging unreliable or royalist elements. Many regiments would march with new commanders or, in the case of 4th Lancers and 50th Line, entirely new officer corps.

Knowing that the first threat would come from the Duke of Wellington’s Anglo-Dutch-German and Field Marshal Gebhard Leberecht von Blücher’s Prussian armies in the Low Countries, in late March Napoleon created corps of observation along the frontier, ordering regiments to field two 600-strong “war battalions” and to mobilize their third and fourth battalions when enough men arrived. On April 30, Napoleon merged these formations into the Armée du Nord. It initially comprised I, II, III, and VI army corps and a cavalry reserve, with IV Corps and the Imperial Guard joining them at the campaign’s opening. The army’s chief of staff was the talented field commander Marshal Jean-de-Dieu Soult, although he had not fulfilled a staff role since the wars of the Revolution.

By late May, despite a mediocre response to Napoleon’s call for men, the frontline regiments all had at least two full battalions. There were losses of ten men per battalion to reform the Imperial Guard, a dozen or so from each battalion for the woefully undermanned artillery train, and a few inevitable desertions, but returning veterans and transfers from reserve formations made up the numbers. Where numbers were still short, Napoleon authorized the use of mobile columns to sweep the countryside for veterans who had not returned voluntarily. Colonels drilled their men thrice weekly, ensuring that even the youngest and most out-of-practice soldiers could perform maneuvers satisfactorily.

Napoleon’s army of 1815 has often been mischaracterized, with opposing claims that it was either entirely composed of grizzled veterans, or a largely raw and inexperienced force. Neither is wholly accurate. Although mostly conscripted soldiers, the majority had served in at least one previous campaign. Across the line infantry, around one in every 100 men had been in service since the 1790s, and more than one in ten for a decade or more. The median first year of service was around 1812, ranging from 1808 in the 5th Regiment to 1813 in the 17th, 19th, 21st, and 45th. The average age of infantrymen was 24. Perhaps a quarter of all men were returned prisoners of war.

Most regiments enjoyed a reasonable degree of internal cohesion. Despite amalgamations and routine transfers between units, almost one-third of men had been in their regiment for at least three years, and each regiment had a core of 50 to 100 soldiers who had been in its ranks for a decade or more. Despite a potential brittleness in adversity among those who had served only through the years of defeat after 1812, these solid foundations allowed new arrivals to bed in quickly and would be crucial to solidity in battle. A notable exception was the Imperial Guard. Only the Grenadiers were veteran battalions; ten new regiments of Young Guard were created on April 8, three regiments of Chasseurs-à-Pied on April 21, and the 4th Chasseurs created only on May 21. Men were drawn from the line infantry, volunteers, and recalled old soldiers. Almost all were veterans, but they had little time to get to know one another or to develop any kind of esprit de corps.

There were also some soldiers with no previous active service. In all, around 1 percent of the army were new volunteers. Other men had been in the army for a year or more but had remained in depots or on garrison duty; the 45th, for example, marched in 1815 with at least 236 rank and file — fully one-quarter of its men — never having been on campaign.

The Armée du Nord’s generals were a mixed bag, which would impact the smooth coordination of the force in combat. In lieu of marshals, most of whom had not returned to service, Napoleon appointed experienced generals to command the army corps. Yet few top-drawer divisional or brigade commanders were available. Only two of four divisional commanders in I Corps, for example, had any experience of leading divisions on campaign. Brigade commanders were usually reasonably solid but were often appointed at the last minute. In late May, the Comte d’Erlon complained that he still did not have enough generals to command I Corps’ brigades. With such last-minute appointments, there were no brigade-strength training exercises to encourage coordination between units or to get generals used to commanding their troops.

Arriving at Waterloo

Waterloo, on June 18, 1815, was the third battle in four days of campaigning. The brief operations over June 15–17 highlighted both the strengths and the very real weaknesses of the French army. By dint of hard marching, the heavily outnumbered French army put itself between Wellington and Blücher’s forces, and in a hard-fought attritional victory over the Prussians at Ligny and drawn battle against Wellington at Quatre Bras on June 16, the individual soldiers showed immense tenacity, courage, and devotion to the cause. Yet the coordination of different arms, and indeed sometimes of units within the same brigade, division, or corps, was frequently deficient. Staff work was poor. Most infamously, this caused d’Erlon’s I Corps to march fruitlessly back and forth between Quatre Bras and Ligny, when committing at either battle might have delivered a shattering French victory. Napoleon himself was partially responsible and showed lethargy at key moments, not least in hesitating to send Marshal Emmanuel de Grouchy in pursuit of Blücher’s beaten troops until it was too late to shepherd them away from Wellington. There were also problems with supply, including a panic in the ill-managed transport train on June 16 that led to food shortages. The troops’ response — to pillage the countryside and their own wagons — further highlighted the poor discipline and lack of cooperation with officers that lurked in even the most veteran units. The Imperial Guard proved so lawless on the night of June 17 that the army’s police commander resigned on the spot.

These strengths and weaknesses would be replicated on the field of Waterloo. Despite their problems, French soldiers entered the battle in good spirits. Most troops waking on June 18 believed they were winning the campaign and expected to be in Brussels by midday. Only when they began to draw up opposite Wellington’s army did many realize that battle was imminent. It is often said that the mud of Waterloo, caused by a torrential rainstorm that lasted from early afternoon on June 17 until dawn the next day, prevented Napoleon’s army from maneuvering until late morning. The more prosaic truth is that the army was spread out after the previous day’s march, and it simply took time for the troops to gather. II Corps began the day some way from the battlefield and would not be in position until mid-morning. VI Corps was farther back still. Troops might have moved earlier, but it was vital to allow tired men time to cook their meager morning soup. Moving the heavy guns of the artillery across sodden ground was certainly a challenge, but it was not the reason for the battle’s delayed start.

By late morning, most troops were nevertheless in position, with I Corps’ four virtually unused divisions on the right, II Corps’ three divisions on the left, the cavalry behind them, and VI Corps and the Imperial Guard in reserve. In all, Napoleon boasted around 72,000 men and 246 guns. Although enjoying only parity in infantry and a slight advantage in cavalry, tireless efforts to rebuild the artillery train in the weeks before the campaign meant that the French army enjoyed an advantage of around 90 guns at Waterloo.

The Battle

Napoleon knew that he needed to beat Wellington before Blücher could come to his ally’s assistance, so his initial plan was straightforward: he would use his artillery advantage to soften up the allied center-left, and then smash through with I Corps’ infantry, supported by II and VI Corps. Once Wellington’s line was broken, the cavalry could be unleashed.

In the distribution of these orders, however, we see some of the problems that beset French command in 1815. Soult, inexperienced as chief of staff, was slow to translate Napoleon’s plans into written instructions, and no sooner were orders written than Napoleon verbally made changes, sending Marshal Michel Ney to explain these to corps commanders. Flexibility is an asset in warfare, but Napoleon’s tinkering smacked more of indecision, and the propensity for verbal commands to contradict written orders simply led to confusion. One of the clearest examples is the day-long engagement around Hougoumont on the French left, which would ultimately draw half of II Corps into a largely unplanned and pointless struggle.

If poor staff work hampered the French army at Waterloo, the slowness of transmitting orders also contributed to Grouchy’s failure to prevent the Prussian army marching to Wellington’s aid. According to Napoleon’s later account, just before I Corps’ attack, a Prussian corps hove into view some miles off to the right, marching unmistakably toward the battlefield. VI Corps was therefore directed to screen this new threat, rather than supporting d’Erlon’s attack. Some blame Grouchy for failing to intercept this Prussian force, but he was exactly where Napoleon’s last orders had placed him. New orders would not reach Grouchy’s sizeable detachment until mid-afternoon, when it was already far too late.

The day’s first major attack failed not because of Grouchy or the distant Prussians, but because of tactical failings at Waterloo. Even with VI Corps unavailable, Napoleon failed to use two unengaged divisions of II Corps (or the guard, or sufficient cavalry) to support I Corps. The attack was also launched in four great divisional columns, advancing in echelon at intervals of 200 meters. Unusually, the divisions formed columns of division by battalion — columns of a single battalion frontage, eight battalions deep, with each battalion in three ranks.

The formation is generally understood to be a mistake. The columns were unwieldy and hard to maneuver and deploy. They perhaps gave soldiers a sense of solidity in mass, and may have mitigated the inexperience of divisional commanders, but neither Napoleon nor corps commander d’Erlon ever gave a reasoned explanation. Some historians have suggested that the battalion frontage at least gave the French fire superiority, but this misses the mark on two counts. First, unless each column came up against an isolated shrunken enemy battalion, they would enjoy no advantage in muskets. Second, the French army lined up with the tallest men in the front rank and the shortest behind; the average height difference between the ranks of 12 centimeters/4.7 inches (based on analysis of the recorded height of every man in the corps) meant that only the first rank could effectively give fire. Instead of fire superiority, the columns aimed to use sheer weight and intimidation to sweep the allies aside.

It almost worked. Encouraged by the example given by their core of veteran troops, the divisions advanced steadily despite the punishing attention of allied artillery. The weight of the attack drove back a Dutch-Belgian brigade, before the left-hand two columns were stalled by an infantry counterattack. Not so 3rd Division. Arriving in echelon, it began to push back a shrunken British brigade — the last infantry reserve on the allied left — and was on the cusp of a breakthrough when, with impeccable timing, two brigades of British heavy dragoons swept forward in counterattack. The giant columns should have offered some protection against horsemen, but in the smoke and confusion, with many senior battalion officers lost during the advance, they did not react in time to close gaps in their ranks. Three divisions shattered almost instantly. Regiments that had been steadfast in attack proved highly brittle in adversity, and all cohesion and order quickly vanished. Once broken, even experienced infantrymen were no match for cavalry, and soon thousands of men were fleeing for their lives. Although a counterattack of cuirassiers and lancers ultimately ended the British cavalry’s marauding, d’Erlon’s infantry suffered appalling casualties, perhaps 5,000 in all, and several French artillery batteries were badly cut up.

This failure of the infantry was matched later in the afternoon by a failure of the cavalry, which charged to exploit a supposed gap in the allied center-right. The famous massed cavalry charge shows the French soldiers’ commitment and courage, but also demonstrates again the weaknesses in discipline and leadership of the makeshift army. Although initially intended to involve a single cavalry corps, ever more horsemen moved forward to join the fray; first-hand accounts differ on who, if anyone, gave such orders, but the upshot was that it engulfed a significant portion of Napoleon’s cavalry reserve, including the Imperial Guard. Moreover, instead of riding down helpless fleeing foes, they found stoic allied infantry in impenetrable squares, which poured murderous musketry into the hapless horsemen. Apparently undaunted, the cavalry rallied and charged again and again, but without support, they were simply squandered against the allied squares. Their few batteries of horse artillery, which should have done great slaughter against tightly packed infantry, were silenced by enemy fire almost as soon as they deployed, and the batteries on the French ridge could not give effective fire support for fear of hitting their own men. Infantry of II Corps was ordered forward but could not get to the enemy past their own swirling horsemen. Perhaps a microcosm of the army’s operations in 1815, the cavalry charges showed fabulous courage, but uncertain command and control, coordination, and discipline.

Slightly more successful were attempts to fend off the newly arrived Prussian vanguard on the far right of the battlefield. Even as the cavalry charged with glorious futility, VI Corps came under heavy pressure from these new foes. To stabilize the situation, Napoleon sent in elements of the Imperial Guard. The ferocious and broken street fighting in Plancenoit village required individual courage and tenacity rather than firm command or cohesion, suiting the newly formed guard regiments perfectly, and the Prussians were temporarily driven back.

Denouement

The grand final act of the battle — a desperate attempt by Napoleon’s elite Imperial Guard to smash Wellington’s center-right — ultimately highlights both the French army’s fighting spirit in attack and its relative brittleness in adversity. The assault, supported by the remnants of I and II Corps, comprised ten guard battalions, almost Napoleon’s whole reserve. The first to strike, in the center of the attack, were four battalions of the 3rd and 4th Chasseurs-à-Pied. The 4th Chasseurs had only been formed a matter of days, and the 3rd only four weeks longer. They were brave men, but without cohesion or any pronounced esprit de corps, the units were less solid than they might have been. Charging with audace, they overran an artillery battery and pushed back a shaken British brigade, but were held by the British Foot Guards in a stern firefight. With mounting casualties and several key officers killed, their cohesion broke, and they were driven back.

To their right, three battalions of the Grenadiers of the Guard, veteran units that had remained intact during Napoleon’s exile, hit the allies at a weak spot. With some horse artillery and cavalry support, these experienced fighters carved a significant hole in the enemy lines. Yet they took brutal losses from musketry and short-range artillery, and were simply too few in number to resist a counterattack by a whole fresh Dutch-Belgian division. At the same time, on the left of the attack, two battalions of Chasseurs and one of Grenadiers hit the brigade of British Foot Guards that had just repulsed the 3rd and 4th Chasseurs. Another ferocious firefight ensued, but a counterattack into their flank soon drove the last of the Imperial Guard and supporting elements of II Corps back down the slope.

With no more reserves, and with the Prussians breaking through to the right-rear, the day was lost. It was not the case, however, that the guard’s repulse caused the French army to disintegrate. In reality, the smoke and rolling terrain meant that most French troops saw little of that event. It was the pincer movement of Wellington’s general counterattack alongside the Prussian breakthrough that caused the rout of Napoleon’s final army. A makeshift force it may have been, but it had taken a day of vicious and sustained combat to break French spirits. Yet the French soldiers were exhausted; without reserves to rally them, and with effective coordination beyond regimental level disintegrating, many units broke as the allied attack gained momentum. As night closed in, the surviving French soldiers fled southward, leaving some 25,000 of their comrades dead, dying, or wounded on the field of Waterloo.

Waterloo was, as Wellington himself confessed, “a near-run thing,” but in the end the battle proved a ridge too far for Napoleon’s army. The mostly veteran soldiers showed enormous personal courage and devotion to their emperor, but the army as a whole suffered from some significant weaknesses.

At the top, it was hampered by an inexperienced and disorganized general staff, exacerbated by Napoleon’s own uncharacteristic indecisiveness and tactical errors at army and corps level. Too many of the army’s middle-ranking generals were inexperienced, and many were appointed too late to get to know their commands properly. The army lacked coordination, and general discipline was poor. Most regiments enjoyed a degree of cohesion, but a significant proportion of the men had only recently joined their unit and lacked the connections of comradeship that could keep men going even in defeat. The supposedly elite Imperial Guard especially was a mostly cobbled-together force. Confidence in the emperor and in their own élan went some way to papering over the cracks, but units across the army proved brittle in adversity. The most surprising thing is perhaps not that they ultimately lost, but that they came so close to victory at all.

Dr. Graeme Callister is senior lecturer in history and war studies at York St. John University, with a current research focus on the French army in the Napoleonic Wars. He is author of War, Public Opinion, and Policy (Palgrave Macmillan, 2017) and co-author of Battle: Understanding Conflict from Hastings to Helmand (Pen & Sword, 2022). He is a regional co-chair of the British Battlefields Trust and fellow of the Royal Historical Society. His latest book, Waterloo: The Attack of I Corps, will be published by Pen & Sword in September 2024. 

Image: Anne S.K. Brown Collection

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