Action at Genappe

Waterloo Campaign: Quatre Bras to Waterloo
Part of The Waterloo Campaign
A portion of Belgium with some places marked in colour to indicate the initial deployments of the armies just before the commencement of hostilities on 15 June 1815: red Anglo-allied, green Prussian, blue French
Date 17 June 1815 Location From Quatre Bras through Genappe to Waterloo in, Belgium Result The Anglo-allied army retreats and the French advance
Belligerents
France	Seventh Coalition:  United Kingdom  Netherlands Hanover  Nassau Brunswick
Commanders and leaders
Napoleon, Marshal Ney	Duke of Wellington and Earl of Uxbridge
Strength
French Army Order of Battle	Anglo-allied army Order of Battle

After the fighting at Quatre Bras (16 June 1815) the two opposing commanders Marshal Ney and the Duke of Wellington initially held their ground while they obtained information about what had happened at the larger Battle of Ligny. When they received intelligence that the Prussian army under the command of Prince Blücher had been defeated by the French Army of the North under the command of Napoleon Bonaparte.

Upon receiving this news Wellington organised the retreat of the Anglo-allied army to a place he had identified a year before as the best place in Belgium for him to be able to employ his reverse slope tactics when fighting a major battle: the escapement close to the village of Waterloo.

Aided by thunderstorms and torrential rain, Wellington's army successfully extricated itself from Quatre Bras and passed through the defile of Genappe. The infantry marched ahead and were screened by a large cavalry rearguard. The French harried Wellington's army, but were unable to inflict any substantial casualties before night fell and Wellington's men were ensconced in bivouacs on the plain of Mont-Saint-Jean.

After the fighting at Quatre Bras, the two armies settled down for the night. The Anglo-allied army on the field of battle and the French just to the south. The bivouac on the battle field of Quatre Bras, during the night of 16 June, continued undisturbed until about an hour before daylight, when a cavalry patrol having accidentally got between the adverse pickets near Piermont, caused an alarm in that quarter that was quickly communicated to both armies by a rattling fire of musketry, which, rapidly augmenting, extended itself along the line of the advanced posts. Among the first who hastened to ascertain the origin and nature of the engagement was Picton, who, together with other staff officers, as they arrived in succession, on discovering that no advance had been attempted or intended on either side, soon succeeded in restoring confidence. Similar exertions were successfully made on the part of the French officers, and as day began to break upon the scene, both parties resumed their previous tranquillity. In this untoward affair, the pickets furnished by the 1st Hanoverian Brigade (Kielmansegg's), and by the 3rd Brunswick Light Battalion (Ebeling's) were sharply engaged, and a pickets of the Field Battalion Bremen (Langrehre's) suffered considerably.

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Wikipedia