A French army under the command of Napoleon Bonaparte is defeated by British forces under the command of Arthur Wellesley, 1st Duke of Wellington of Dublin and a Prussian army under the command of Field Marshal Gebhard Leberecht von Blücher. The Iron Duke is not the only Irish presence on the battlefield that day. Napoleon’s horse, Marengo, is reared in County Wexford, and the Duke of Wellington’s mount is from County Cork.
Upon Napoleon’s return to power in March 1815, many states that have opposed him form the Seventh Coalition and begin to mobilise armies. Wellington and Blücher’s armies are cantoned close to the northeastern border of France. Napoleon chooses to attack them separately in the hope of destroying them before they can join in a coordinated invasion of France with other members of the coalition. On June 16, he successfully attacks the bulk of the Prussian army at the Battle of Ligny with his main force, while a portion of the French army simultaneously attacks the Anglo-allied army at the Battle of Quatre Bras. Despite holding his ground at Quatre Bras, the defeat of the Prussians forces Wellington to withdraw north to Waterloo on June 17. Napoleon sends a third of his forces to pursue the Prussians, who have withdrawn parallel to Wellington in good order. This results in the separate and simultaneous Battle of Wavre with the Prussian rear-guard.
Upon learning that the Prussian army is able to support him, Wellington decides to offer battle on the Mont-Saint-Jean escarpment across the Brussels road. Here he withstands repeated attacks by the French throughout the afternoon of June 18, aided by the progressively arriving Prussians. In the evening, Napoleon commits his last reserves, the senior battalions of the French Imperial Guard infantry. The desperate final attack of the Guard is narrowly beaten back. With the Prussians breaking through on the French right flank, Wellington’s Anglo-allied army counter-attacks in the centre, and the French army is routed.
Waterloo is the decisive engagement of the Waterloo Campaign and Napoleon’s last. Napoleon abdicates four days later, and coalition forces enter Paris on July 7. The defeat at Waterloo ends Napoleon’s rule as Emperor of the French and marks the end of his Hundred Days return from exile. This ends the First French Empire and sets a chronological milestone between serial European wars and decades of relative peace.
The battlefield is located in the municipalities of Braine-l’Alleud and Lasne, about 15 kilometres south of Brussels, and about 2 kilometres from the town of Waterloo. The site of the battlefield today is dominated by the monument of the Lion’s Mound, constructed from earth taken from the battlefield itself. The topography of the battlefield near the mound has not been preserved.