The Waterloo campaign, also known as the Belgian campaign (15 June – 8 July 1815) was fought between the French Army of the North and two Seventh Coalition armies, an Anglo-allied army and a Prussian army. Initially the French army had been commanded by Napoleon Bonaparte, but he left for Paris after the French defeat at the Battle of Waterloo. Command then rested on Marshals Soult and Grouchy, who were in turn replaced by Marshal Davout, who took command at the request of the French Provisional Government. The Anglo-allied army was commanded by the Duke of Wellington and the Prussian army by Field Marshal Graf von Blücher.
The war between France and the Seventh Coalition came when the other European Great Powers refused to recognise Napoleon as Emperor of the French upon his return from exile on the island of Elba, and declared war on him, rather than France, as they still recognised Louis XVIII as the king of France and considered Napoleon a usurper. Rather than wait for the Coalition to invade France, Napoleon decided to attack his enemies and hope to defeat them in detail before they could launch their combined and coordinated invasion. He chose to launch his first attack against the two Coalition armies cantoned in modern-day Belgium, then part of the newly formed United Kingdom of the Netherlands, but until the year before part of the First French Empire.
Hostilities started on 15 June when the French drove in the Prussian outposts and crossed the river Sambre at Charleroi placing their forces between the cantonment areas of Wellington's army (to the west) and Blücher's army to the east. On 16 June the French prevailed with Marshal Ney commanding the left wing of the French army holding Wellington at the Battle of Quatre Bras and Napoleon defeating Blücher at the Battle of Ligny. On 17 June, Napoleon left Grouchy with the right wing of the French army to pursue the Prussians while he took the reserves and command of the left wing of the army to pursue Wellington towards Brussels.
On the night of 17 June the Anglo-allied army turned and prepared for battle on a gentle escarpment, about south of the village of Waterloo. The next day the Battle of Waterloo proved to be the decisive battle of the campaign. The Anglo-allied army stood fast against repeated French attacks, until with the aid of several Prussian corps that arrived at the east side of the battlefield in the early evening they managed to rout the French army. Grouchy with the right wing of the army engaged a Prussian rearguard at the simultaneous Battle of Wavre, and although he won a tactical victory his failure to prevent the Prussians marching to Waterloo meant that his actions contributed to the French defeat at Waterloo. The next day (19 June) he left Wavre and started a long retreat back to Paris.
Following the defeat at Waterloo, Napoleon chose not to remain with the army and attempt to rally it, but returned to Paris to try to secure political support for further action. He failed to do so, and was forced to abdicate on 22 June. Two days later, a Provisional Government took over French politics. Meanwhile, the two Coalition armies hotly pursued the French army to the gates of Paris, during which the French on occasion turned and fought some delaying actions, in which thousands of men were killed.
Initially the remnants of the French left wing and the reserves that were routed at Waterloo were commanded by Marshal Soult while Grouchy kept command of the right wing. However, on 25 June Soult was relieved of his command by the Provisional Government and was replaced by Grouchy, who in turn was placed under the command of Davout.
When the French Provisional Government realised that the French army under Marshal Davout was unable to defend Paris, they authorised delegates to accept capitulation terms which led to the Convention of Saint-Cloud (the surrender of Paris) which ended hostilities between France and the armies of Blücher and Wellington.
The two Coalition armies entered Paris on 7 July. The next day Louis XVIII was restored to the French throne, and a week later on 15 July Napoleon surrendered to Captain Frederick Lewis Maitland of . Napoleon was exiled to the island of Saint Helena where he died on 5 May 1821.
Under the terms of the peace treaty of November 1815, Coalition forces remained in Northern France as an army of occupation under the command of the Duke of Wellington.
Prelude
Napoleon returned from his exile on the island of Elba on 1 March 1815, King Louis XVIII fled Paris on 19 March, and Napoleon entered Paris the next day. Meanwhile, far from recognising him as Emperor of the French, the Great Powers of Europe (Austria, Great Britain, Prussia and Russia) and their allies, who were assembled at the Congress of Vienna, declared Napoleon an outlaw, and with the signing of this declaration on 13 March 1815, so began the War of the Seventh Coalition. The hopes of peace that Napoleon had entertained were gone – war was now inevitable.
A further treaty (the Treaty of Alliance against Napoleon) was ratified on 25 March in which each of the Great European Powers agreed to pledge 150,000 men for the coming conflict. Such a number was not possible for Great Britain, as her standing army was smaller than the three of her peers. Besides, her forces were scattered around the globe, with many units still in Canada, where the War of 1812 had recently ceased. With this in mind she made up her numerical deficiencies by paying subsidies to the other Powers and to the other states of Europe that would contribute contingents.
Some time after the allies began mobilising, it was agreed that the planned invasion of France was to commence on 1 July 1815, much later than both Blücher and Wellington would have liked as both their armies were ready in June, ahead of the Austrians and Russians; the latter were still some distance away. The advantage of this later invasion date was that it allowed all the invading Coalition armies a chance to be ready at the same time. Thus they could deploy their combined numerically superior forces against Napoleon's smaller, thinly spread forces, thus ensuring his defeat and avoiding a possible defeat within the borders of France. Yet this postponed invasion date allowed Napoleon more time to strengthen his forces and defences, which would make defeating him harder and more costly in lives, time and money.
Napoleon now had to decide whether to fight a defensive or offensive campaign. Defence would entail repeating the 1814 campaign in France but with much larger numbers of troops at his disposal. France's chief cities, Paris and Lyon, would be fortified and two great French armies, the larger before Paris and the smaller before Lyon, would protect them; francs-tireurs would be encouraged, giving the Coalition armies their own taste of guerrilla warfare.
Napoleon chose to attack, which entailed a pre-emptive strike at his enemies before they were all fully assembled and able to co-operate. By destroying some of the major Coalition armies, Napoleon believed he would then be able to bring the governments of the Seventh Coalition to the peace table to discuss results favourable to himself, namely peace for France with himself remaining in power as its head. If peace were rejected by the allies despite any pre-emptive military success he might have achieved using the offensive military option available to him, then the war would continue and he could turn his attention to defeating the rest of the Coalition armies.
Napoleon's decision to attack in Belgium was supported by several considerations. First, he had learned that the British and Prussian armies were widely dispersed and might be defeated in detail. The other major coalition armies of Russia and Austria would not be able to reinforce the Prussians and British. This was because the Russian army was still moving across Europe and the Austrian army was still mobilising. Also, the British troops in Belgium were largely second-line troops; most of the veterans of the Peninsular War had been sent to America to fight the War of 1812. In addition, the army of the United Netherlands was reinforcing the British. These Dutch troops were ill-equipped and inexperienced. And, politically, a French victory might trigger a pro-French revolution in French-speaking Belgium.
Deployments
French forces
During the Hundred Days both the Coalition nations and Napoleon mobilised for war. Upon resumption of the throne, Napoleon found that he was left with little by Louis XVIII. There were 56,000 soldiers of which 46,000 were ready to campaign. By the end of May the total armed forces available to Napoleon had reached 198,000 with 66,000 more in depots training but not yet ready for deployment.
Napoleon placed some corps of his armed forces at various strategic locations as armies of observations. Napoleon split his forces into three main armies; first, he placed an army in the south near the Alps. This army was to stop Austrian advances in Italy. Second, there was an army on the French/Prussian border where he hoped to defeat any Prussians attacks. Last, the L'Armee du Nord was placed on the border with the United Netherlands to defeat the British, Dutch and Prussian forces if they dared to attack. (see Military mobilisation during the Hundred Days). Lamarque led the small Army of the West into La Vendée to quell a Royalist insurrection in that region.
By the end of May Napoleon had formed L'Armée du Nord (the "Army of the North") which, led by himself, would participate in the Waterloo campaign and had deployed the corps of this army as follows: I Corps (D'Erlon) cantoned between Lille and Valenciennes. II Corps (Reille) cantoned between Valenciennes and Avesnes. III Corps (Vandamme) cantoned around Rocroi. IV Corps (Gérard ) cantoned at Metz. VI Corps (Lobau) cantoned at Laon. I, II, III, and IV Reserve Cavalry Corps (Grouchy) cantoned at Guise. Imperial Guard (Mortier) at Paris.
Once the campaign was underway Napoleon, on the evening of 15 June, would send Marshal Ney with the left wing of the army (I and II corps) to face Wellington at Quatre Bras. During the morning of 17 June Napoleon detached the right wing (III and IV corps) under Marshal Grouchy to pursue the retreating Prussians (who retreated to Wavre), while he led the reserves (Imperial Guard, VI Corps, and I, II, III, and IV Cavalry Corps) to rejoin Ney's detachment and pursue Wellington to Waterloo.
Coalition forces In the early days of June 1815, Wellington and Blücher's forces were disposed as follows:
Wellington's Anglo-allied army of 93,000 with headquarters at Brussels were cantoned: I Corps (Prince of Orange), 30,200, headquarters Braine-le-Comte, disposed in the area Enghien-Genappe-Mons. II Corps (Lord Hill), 27,300, headquarters Ath, distributed in the area Ath-Oudenarde-Ghent. Reserve cavalry (Lord Uxbridge) 9,900, in the valley of the Dendre river, between Geraardsbergen and Ninove. The reserve (under Wellington himself) 25,500, lay around Brussels. The frontier in front (to the west) of Leuze to Binche was watched by Dutch light cavalry.
Blücher's Prussian army of 116,000 men, with headquarters at Namur, was distributed as follows: I Corps (Graf von Zieten), 30,800, cantoned along the Sambre, headquarters Charleroi, and covering the area Fontaine-l'Évêque-Fleurus-Moustier. II Corps (Pirch I), 31,000, headquarters at Namur, lay in the area Namur-Hannut-Huy. III Corps (Thielemann), 23,900, in the bend of the river Meuse, headquarters Ciney, and disposed in the area Dinant-Huy-Ciney. IV Corps (Bülow), 30,300, with headquarters at Liège and cantoned around it.
The frontier in front of Binche, Charleroi and Dinant was watched by the Prussian outposts.