The Paoli Massacre is the name given to an incident during the American Revolutionary War. Following the Battle of Brandywine on September 11, 1777, Brigadier General Anthony Wayne was forced to retreat with his troops to Chester, Pennsylvania in Delaware County.

In the following days, the British forces continued to advance on Philadelphia and Wayne's 1,500 troops attempted to harass the enemy. Wayne assumed that their presence was undetected and camped close to the British lines.

On September 20-21, the British commander Major General Charles Grey undertook a skillful night attack in which the British surprised the sleeping American soldiers, attacking with bayonet killing 53 and wounding over 100.

An official inquiry found that Wayne was not guilty of misconduct but had made a tactical error. Wayne was enraged and demanded a full court-martial. On November 1, a board of 13 officers declared that Wayne had acted with honor.

The incident gained some notoriety, with rumors that the British had stabbed or burned Americans who tried to surrender making martyrs out of the casualties. The British troops came to fear revenge by Mad Anthony Wayne's troops.