Early on the morning of 15 June 1815 the Prussian commander at Charleroi, Hans Ziethen, awoke to the distant booming of cannon south of the town. For the past several days he had received various reports of heavy enemy concentrations along his front, yet had not been particularly concerned; informed opinion held that the French would not be ready for action for another month, by which time the Allies–who had scheduled their advance for 27 June–would in all probability be across the Aisne. Such was Ziethen’s confidence that when a French deserter arrived on the 12th warning of a major offensive, the Prussian commander scoffed at the idea, making no effort to investigate and letting an entire day go by before reporting the incident to headquarters. Now, as the first light of day revealed dark columns of smoke along the southern horizon, he realized his error.
By 8 a.m., with French cavalry beginning to arrive on the south bank of the Sambre opposite the town, Ziethen had managed to assemble sufficient troops to secure the river bridges and hold them off. His forwardmost units had been completely overrun, however, and much of his command was falling back in confusion. The French, meanwhile, were experiencing problems of their own, for no sooner had their leading columns made a start than they became entangled along narrow, rain-soaked country roads that quickly turned to quagmires beneath their feet. Fuming at the holdup, Napoleon pulled units of his Guard out of line and sent them around the traffic jam, determined to keep up the pressure on the fleeing enemy. Once again, as in the earliest days of his career, the ‘Little Corporal’ seemed to be everywhere at once, leading, coaxing, goading the army into motion.
By noon, the Guard had swept forward despite increasingly stubborn opposition, eventually driving Ziethen out of Charleroi and establishing bridgeheads there and some two miles west of the town at Marchienne-au-Pont. As the army streamed across the Sambre, Napoleon set up headquarters along the Brussels highway and developed his plans. At this point, with the Anglo-Dutch army lying to the northwest and the main body of the Prussians to the northeast, the French advance would be obliged to proceed on two fronts. Marshal Ney, in charge of three corps, would continue up the Brussels highway upon Quatre-Bras, while the rest of the army turned eastward, driving the Prussians back upon Sombreffe. His plans complete, Napoleon continued to be omnipresent, now overseeing Ney’s operations in front of Gosselies, now racing east to send his cavalry against Ziethen at Gilly. For the time being, with his two columns within an hour’s ride of each other, he managed to assert a remarkable degree of personal control, and by 6 p.m. his initial objectives on both fronts had been taken. Pressing forward, Marshal Ney came upon the first organized Anglo-Dutch resistance near Frasnes. Meanwhile, Vandamme advanced as far as the outskirts of Fleurus before Ziethen’s stubborn delaying tactics forced him to halt. Thus, despite a series of unforeseen delays, the first day of the campaign had carried the French roughly halfway to Brussels and taken both Allied commanders completely by surprise.
In fact, the full extent of the French incursion had not become clear to the Duke of Wellington until the early hours of the 16th. Earlier in the day he had shown little concern over preliminary reports of French activity to the south, still convinced that the enemy’s main effort would be made against his right at Tournai. Meanwhile, in an effort to reassure the local population, he made a point of attending a lavish ball given by the Duchess of Richmond in the Belgian capital, where fresh accounts of the day’s fighting reached him sometime after midnight. Suddenly realizing his danger, he ordered the army’s reserve to march south without delay. The party was brought to an abrupt end, and whatever panic the royalist population of Brussels may have felt was entirely justified.
On the morning of the 16th Napoleon took up very much where he had left off the previous day, directing Ney and Grouchy to advance on Quatre-Bras and Sombreffe respectively. While the enemy scrambled to assemble sufficient forces to defend both positions, the French still enjoyed a clear advantage in numbers, and the two wings of the army were well situated to support each other. The men themselves had been worn down by the previous day’s fighting and marching, however, and the morning would pass before they were prepared to attack.
Meanwhile, the Allied commanders had rushed to the scene in advance of their troops. About noon Blücher and Wellington held a meeting near Sombreffe in which they quickly agreed to support each other. Precisely how this might be accomplished was not clear. Wellington’s troops were outnumbered at least four to one in front of Quatre-Bras, and whereas Blücher had managed to assemble three Prussian corps, his dispositions were not promising. Having abandoned Fleurus in the early hours of the morning, Ziethen was drawn up in a cluster of villages surrounding Ligny, where, despite the presence of reinforcements in nearby Sombreffe, his troops were in danger of being enveloped. With the bulk of the French forces in front of the Prussians at Ligny and Ney poised to occupy Quatre-Bras, Napoleon developed his plans for the day with an eye to destroying the Prussians before turning his full attention on the Anglo-Dutch army. Having as yet little opposition in his front, Ney was ordered to seize the strategic crossroads and turn southeast along the highway to Namur. This would lead him directly into the Prussian rear at Brye, at which point, fully engaged in front and flank at Ligny, Blücher’s army would be surrounded and, if all went well, caught in a giant pincer movement.
Throughout the morning Napoleon carefully oversaw the positioning of his troops in front of Ligny, patiently awaiting the chance to spring the trap. At 2:30, with Exelman’s cavalry in front of the Prussian left at Sombreffe, he sent General Gerard forward at Ligny while Vandamme fell on the enemy right at St. Amand. Soon the weakness of the Prussian position became apparent, as Ziethen’s troops lay exposed to a concerted cross-fire of massed French artillery. In response to increasing pressure on their endangered right flank, Prussian reinforcements moved up in support, until much of Blücher’s entire force was within the deadly pocket Napoleon had prepared for them. Now it remained only for Ney to strike from the direction of Quatre-Bras to seal the fate of Blücher’s army.
Meanwhile, however, Ney was only just beginning to move against the thin enemy line at Quatre-Bras, and what he might have accomplished with ease earlier in the day would becoming increasingly difficult with the passage of time. By two o’clock Wellington had returned from his meeting with Blücher, arriving just in time to repel an assault on his left flank near Pireaumont. Shortly thereafter, the Duke narrowly escaped capture when a squadron of French lancers forced him to run for cover amid a regiment of Highlanders. Forced to temporize while his main force continued to arrive from Brussels, the Allied commander made ostentatious use of his existing forces and threw newly arrived units into line as soon as they came up, managing to keep the enemy at bay by the thinnest of margins.
Ney, meanwhile, was awaiting the chance to play a trump card: D’Erlon’s 20,000 fresh troops on the way from Gosselies. Upon their arrival, he would launch his final assault and send Wellington packing. Or so he thought. Things were about to go badly awry for the French cause, however, for even as D’Erlon was approaching Frasnes he was intercepted by a member of Napoleon’s staff with orders to march on the Prussian rear at Brye. (Though D’Erlon would later claim to have received written orders from the Emperor, no such orders were ever found.) Thus, just as the French reserve was about to provide Ney with a deciding force against Wellington, it turned and counter-marched to the southeast.
Despite the disruption to Ney’s plans, D’Erlon’s change of course promised to realize Napoleon’s primary objective, the destruction of the Prussian army, and had the column of reinforcements arrived as planned in Ziethen’s rear, all might have been for the best. Instead, while marching to the sound of the guns at Ligny, D’Erlon veered southward, approaching the fight in rear of Vandamme’s position at St. Amand. The miscalculation proved calamitous, for in the absence of clear communication with the rest of the army, the column was mistaken for an enemy flanking force, quickly spreading panic through the French lines. Fearing that they themselves were about to be enveloped, Vandamme’s men fell back, at which point the Prussians promptly went on the attack, pushing them out of St. Amand and regaining much lost ground.
Next, abandoning any attempt to redeem his ill-fated flanking movement, and again in response to orders of dubious origin, D’Erlon detached two brigades in support of Vandamme and changed his course once more, making his way back toward Ney. By the time his men had completed their five-mile detour, however, the steady arrival of Allied reinforcements at Quatre-Bras had changed the arithmetic in Wellington’s favor, and the opportunity to deliver a decisive blow had been lost. With the day drawing to a close, Ney vented his frustration by launching a reckless cavalry attack, which was bloodily repulsed.
Meanwhile, his plans for crushing Blücher’s army having drifted away with the dust of D’Erlon’s receding troops, Napoleon had regrouped for a final, frontal assault on Ziethen’s position, hoping to cripple the Prussians as much as possible. Moving forward in the gathering dusk, the Old Guard drove across Ligne Creek, smashed through the enemy line and, forming squares, went on to shatter a Prussian cavalry charge led by Blücher himself. Indeed, when the Prussian horsemen were themselves overrun by French cuirasseurs, their commander was nearly killed when his horse was shot from under him. Though he would be rescued through the quick thinking of an aide, his temporary loss caused the Prussians to abandon their positions and flee northward into the gathering darkness.
Thus, although his plans had gone badly awry, with a single sledge-hammer blow at Ligny Napoleon carried the day, dramatically improving his chances of defeating both enemy armies. With the Prussians falling back in confusion, it remained only to shepherd them out of Belgium while he redirected his forces against Wellington’s now-isolated Anglo-Dutch troops. The next day, the 17th, having placed Marshal Grouchy in command of some 33,000 men with orders to pursue Blücher’s fleeing troops, he spent much of the morning mopping up at Ligny. Secure in the knowledge that the Anglo-Dutch army remained fixed at Quatre-Bras, he even took time to visit the wounded in the army’s field hospitals. Then, about noon, he started west from Marbais with plans to fall with overwhelming force on Wellington’s flank.
By this time, however, having learned of Blücher’s defeat at Ligny, Wellington had slipped his lines at Quatre-Bras and was on his way north to reposition his forces for the coming encounter. That he had been able to disengage and retire in the immediate presence of a large covering force clearly reflected badly on Marshal Ney, whose brilliance as a corps commander was thus far showing few signs of carrying over to the larger responsibilities of army command. Incensed at the latter’s failure to actively engage the enemy in his front, Napoleon raced forward in a desperate effort to maintain contact, arriving at Quatre-Bras in time to see the Allied rearguard disappear across the next ridge. Moments later a violent cloudburst loosed fresh torrents of rain on the already-saturated landscape, drowning any hopes of catching up to the fleeing foe. Another shining opportunity had been lost.
Despite this latest blunder, however, the French still stood an excellent chance of defeating the harried Anglo-Dutch army. With Grouchy in pursuit of Blucher’s shattered Prussians and Blücher himself temporarily out of action, he had only to give Wellington another hard shove to send him reeling back upon Brussels, where panic was already taking hold of the city’s royalist community in expectation of a French victory. Throughout the afternoon of the 17th, he hustled his army north, passing Genappe and slogging onward through heavily-trammeled mud in the wake of Wellington’s army. By 6:30 the French vanguard had arrived at a point some four miles south of the village of Waterloo. Here, in front of a small farm settlement known as Mont St. Jean, substantial numbers of enemy troops could be seen along a low ridge running at right angles to the highway. In an effort to determine their strength, Napoleon ordered his cavalry to deploy, but a cannonade of some sixty enemy guns quickly told him what he wanted to know; the troops along the ridge represented Wellington’s main force. Satisfied that the enemy was prepared to stand and fight, Napoleon called back his horsemen and prepared for a major engagement. Throughout the evening the French army continued to arrive opposite Mont St. Jean, taking up positions near a farm known as La Belle Alliance, and as more rain began to fall both armies crawled under canvas to spend a wet and dreadful night.