he Battle of Waterloo was a battle near Waterloo, a town then located in the Southern Netherlands, nowadays in Belgium. Napoleon Bonaparte was posted here June 18 1815 definitely defeated by a coalition of British, Dutch and Hannover units under the supreme command of Wellington and on the other hand a Prussian army under command of Marshal von Blucher.

After being exiled to Elba, Napoleon returned to France in March 1815. He installed himself there again as Emperor of France. His old enemies formed the Seventh Coalition to chase him away again. England and Prussia massed large armies in the southern Netherlands to invade France on July 1, 1815. Napoleon decided to get ahead of them and drew the border of the United Kingdom of the Netherlands about at Charleroi. He hoped to disperse the armies of Wellington and Blücher so that they could be destroyed separately.

His left wing was held up by the Dutch in the Battle of Quatre-Bras. With his right wing he defeated the Prussians the same day in the Battle of Ligny. These withdrew north to continue assisting Wellington. Napoleon pursued the British-Dutch army with his main force on June 17 and had the Prussians followed by Marshal Emmanuel de Grouchy. Wellington took up a defensive position on a ridge south of Waterloo in the hope that the Prussians would come to his aid in time.

After being delayed by heavy rain, Napoleon opened the attack around noon on June 18. Several of these French attacks threatened to break through the Allied left wing, but each time they failed. At the critical moment the Prussians appeared on the French right flank, after which the French army collapsed and fled.

Wellington lost about fifteen thousand men (dead or wounded), Blücher about seven thousand. Napoleon lost roughly twenty-five thousand men, plus thousands of prisoners. Furthermore, large numbers of French deserted after the battle.

Napoleon was forced to abdicate the throne in Paris. The British exiled him to Saint Helena. In the aftermath, France became smaller.