Napoleon commanded approximately 72,000 soldiers at the Battle of Waterloo. Historical estimates vary because researchers count units differently, but the French Army of the North on the battlefield is commonly placed in the low-to-mid 70,000s.
Napoleon’s force included infantry, cavalry and artillery, supported by 254 guns in some modern reconstructions. It was only part of the larger army he had assembled during the Hundred Days. About 33,000 men under Marshal Grouchy had been sent to pursue the retreating Prussians and did not take part in the main battle at Waterloo.
The French army faced Wellington’s Anglo-allied army and the Prussian army commanded by Gebhard von Blücher. Napoleon hoped to defeat the coalition forces separately, but the Prussians reached the battlefield during the afternoon and attacked the French flank. That reinforcement helped turn the battle against him. Figures such as 73,000 or 74,500 also appear in historical accounts, so 72,000 is best understood as a rounded estimate rather than an exact roll call.