Who led the Prussian army that reinforced Wellington at Waterloo?

The Prussian army that reinforced Wellington at Waterloo was led by Gebhard Leberecht von Blücher. A Prussian field marshal, Blücher directed his army toward the battlefield after the Prussians had been defeated by Napoleon at Ligny two days earlier.

Blücher was determined to keep his promise to support Wellington. Despite being injured at Ligny, where he was temporarily trapped beneath his dead horse, he resumed command and ordered the Prussian army toward Wavre and then Waterloo. Its arrival on Napoleon’s exposed right flank became decisive as the battle progressed.

Blücher’s chief of staff, General August Neidhardt von Gneisenau, also played an important operational role, especially during the retreat from Ligny. That sometimes creates confusion over the answer. Gneisenau was a senior planner and second-in-command, but Blücher was the army’s commander. His aggressive reputation earned him the nickname “Marschall Vorwärts,” or “Marshal Forward.”