Battle of Ligny

Background

Napoleon crossed the Belgian frontier before dawn on 15 June 1815, at Thuin and Charleroi, aiming to strike the two Allied armies in Belgium before they could combine: Wellington's Anglo-allied army around Brussels and Blücher's Prussian Army of the Lower Rhine to its east. Zieten's I Corps fought a delaying action back from the Sambre on the 15th and bought time for the Prussians to concentrate.

The Prussian staff had chosen and surveyed a position behind Fleurus long before: the heights of Brye, Sombreffe and Tongrinne, behind the marshy Ligny brook and its chain of stone-built villages. It stood astride the Namur–Nivelles road, which joined it to Wellington at Quatre Bras seven miles away. The plan assumed all four corps, but Bülow's IV Corps, coming from Liège, received its orders late and could not arrive until the night of the 16th. Blücher fought anyway with three corps. He expected Wellington's support down the Namur road, and an orderly retreat while the two armies' lines of communication pointed in opposite directions looked hardly less dangerous than a battle.

Napoleon reached Fleurus late in the morning and decided to fall on the Prussians, whom he took to be the greater threat, while Ney held off Wellington with the left wing at Quatre Bras. He believed Blücher's line faced the wrong way and exposed its right flank, and at 14:00 had Soult write to Ney to beat whatever was in front of him and then turn on the Prussian right and rear. At about 13:00 Wellington rode over from Quatre Bras, met Blücher at the Bussy windmill and promised the support of at least one corps; then he rode back to face Ney.

The armies

Napoleon brought the centre and right wing of the Armée du Nord. Vandamme's III Corps, with Girard's division detached from Reille, faced the western villages of Saint-Amand, Saint-Amand-la-Haye and Wagnelée. Gérard's IV Corps faced Ligny. Grouchy, with Pajol's and Exelmans' cavalry corps, held the long right flank opposite Thielmann. In reserve stood the Imperial Guard and Milhaud's cuirassiers, and Lobau's VI Corps marched up from Charleroi during the afternoon. These were mostly veterans, and the Guard and the cuirassiers were fresh when they were finally thrown in.

Blücher's army was larger but younger. Zieten's I Corps held the villages and the Bussy heights, Pirch I's II Corps stood behind it, and Thielmann's III Corps held the left from Sombreffe to Balâtre. A large part of the infantry were Landwehr and newly raised regiments, many under fire for the first time, and the Rhenish and Westphalian drafts were of doubtful loyalty. Gneisenau, the chief of staff, and Grolman, the quartermaster-general, ran the army's staff work.

The ground favoured the French. Their side of the valley was higher and its folds hid their reserves, while the Prussian supports and reserves stood on open, forward slopes in full view of the French batteries. The villages, with stone farms, walled courtyards and hollow lanes, made the battle a street fight.

The battle

CDB90 records the battle as engagement 143 (LIGNY), from 14:00 to 21:30. Times below come from Siborne, Clausewitz and Wikipedia and are approximate; they differ by up to an hour.

Opening (11:00–14:30). French light troops took Fleurus between 11:00 and noon, and Röder's Prussian cavalry fell back across the brook. The French corps deployed in front of Fleurus: Vandamme on the left opposite Saint-Amand, Gérard in the centre opposite Ligny, Grouchy's cavalry on the right, the Guard and Milhaud in reserve.

Saint-Amand and Ligny (14:30–16:00). At about 14:30 Lefol's division of Vandamme's corps stormed Saint-Amand and drove out its defenders. Steinmetz's brigade retook it with the help of canister from the heights, then lost it again, suffering about 2,300 casualties in a short time. Gérard sent three columns against Ligny from about 15:00; the Prussian battalions behind its walls and hedges threw them all back. Further attacks, with skirmishers creeping up through the tall corn, carried the outer gardens and the churchyard, and the village became a burning ruin, fought over house by house. Girard's division took Saint-Amand-la-Haye on the French left.

Blücher's counter-attacks (16:00–18:00). Blücher went to his right in person to retake Saint-Amand-la-Haye with Pirch II's brigade; Girard was mortally wounded in its defence. He meant to turn the French left from Wagnelée, but Tippelskirch's young battalions were broken by fire from the corn. Saint-Amand-la-Haye changed hands repeatedly, and one by one Blücher fed in Pirch I's brigades until he had almost no reserve. Napoleon sent the Young Guard to support Vandamme. On the left Thielmann and Grouchy fought little more than outpost actions around Tongrinne and Boignée.

D'Erlon (about 17:00–19:00). Napoleon had his Guard moving on Ligny when Vandamme reported a large column approaching his left rear. It was d'Erlon's I Corps, which a staff officer carrying Napoleon's order had turned towards Saint-Amand on its way to Quatre Bras. Vandamme took it for an enemy, Girard's division fell back to cover Fleurus, and Napoleon halted the Guard while he found out. By the time his aide reported, at about 19:00, d'Erlon had received Ney's peremptory recall and was marching away, leaving only his light cavalry and part of his infantry near Wagnelée.

The Guard breaks the centre (about 19:45–21:00). With the Prussian reserves drawn to the right, Napoleon launched the Old Guard and Milhaud's cuirassiers against Ligny behind a heavy bombardment from the Guard batteries, with Gérard's men renewing the attack inside the village. In the rain and failing light the Guard crossed the brook and the cuirassiers came round the village; the Prussian infantry fell back towards Brye in squares. Blücher led a last cavalry charge. His horse was shot, fell and pinned him; French cuirassiers rode past him twice in the dusk, and his aide Nostitz got him away on a uhlan's horse, half-conscious.

Retreat (21:00–03:00). Gneisenau took command and ordered I and II Corps back on Tilly, covered by rearguards at Brye and Sombreffe that held until after midnight. Thielmann, who still held his ground, fell back on Gembloux at about 03:00, where Bülow had arrived. The French bivouacked on the field.

Aftermath

The French lost about 7,000–12,000 men and the Prussians 12,000–16,000 killed and wounded, with 21 guns. Another 8,000 or so recently raised troops from the Rhineland and Westphalia ran for Liège and Aachen in the night. Clausewitz, who served with the Prussian army in the campaign, called Ligny a battle 'which 78,000 men lost to 75,000 by a very slight tipping of the scales'.

It was Napoleon's last victory, but not a decisive one. He did not pursue that night, and Grouchy's pursuit with about 33,000 men did not start until the late morning of the 17th. The Prussians did not retreat east along their own communications towards Namur and Liège, but north by Tilly and Mont-Saint-Guibert to Wavre, where Bülow's fresh IV Corps joined them. From there Blücher could march to Wellington's aid at Waterloo on the 18th, while Thielmann held Grouchy at Wavre.

Who decided on Wavre is still argued. The usual story credits Gneisenau, who ordered the retreat on Tilly while Blücher was missing; Siborne says the Wavre decision was made later that night, and Clausewitz praises Blücher for turning towards Wellington on the 17th. Wellington's promise at the Bussy windmill, and whether he could have kept it, is a second debate; d'Erlon's march between two battles is a third.

Wargaming it

Ligny is a big, grinding battle: over 150,000 men, but most of the fighting packed into a line of villages along one brook. At brigade or division level the whole day fits a large table. At battalion level Saint-Amand, Saint-Amand-la-Haye and Ligny each make a good scenario, with house-by-house fighting, fresh battalions fed in as others burn out, and village sectors that change hands again and again.

The terrain sets the puzzle. The villages are fortresses for whoever holds them, but the Prussian reserves stand on open slopes that the French guns can see, while the French reserves are hidden. Tall corn hides skirmishers, and the brook's bed is soft and swampy in places. Thielmann's wing is mostly a waiting game against Grouchy's cavalry, so the player there has to decide whether to attack.

The decisions are about timing. The Prussian player must decide how long to feed the villages and whether to counter-attack the French left; the French player when to commit the Guard. The great what-if is d'Erlon: an arrival table for I Corps that might fall on the Prussian right at 17:00, appear and leave, or never come keeps both players guessing. Others are Wellington sending help down the Namur road, or Bülow arriving during the afternoon. Judge the Prussian player on getting the army away intact, not only on holding the field.

Maps and pictures

Paintings and prints

Paintings and prints of the battle, from the time and the century after, by year: free-to-use pictures from the battle's category on Wikimedia Commons. Each opens its file page there, with the full caption and source.