The Battle of Monmouth occurred on June 28, 1778 when General George Washington's Continental Army attacked the troops of General Sir Henry Clinton's British Army. The week before, General Clinton had begun evacuating his troops out of Philadelphia to move to New York. The move was precipitated by the entry of the French into the war on the American side. Following the evacuation, General Washington reentered Philadelphia and left Brigadier General Benedict Arnold in command.
General Washington sent several units to follow the British Army and try to slow its progress to New York through harassment and skirmishes. Washington's goal was to engage and defeat the British army before it reached New York. The British Army had taken a southerly route to New York, and by June 24, the Continental Army was on the move along a northerly route. The routes intersected in Monmouth, New Jersey.
The American army outnumbered the British two-to-one. However, Major General Charles Lee who led the initial attack on the rear flank of the British Army did not execute the battle plan. For whatever reason, ill-preparation, lack of enemy intelligence, lack of confidence in his soldiers, his forces ended up in retreat. General Clinton's British infantry pursued the fleeing Americans.
What was a promising opportunity was devolving into a disaster. Washington requested a report from Major General Lee, and not satisfied with the response, approached the fighting, where he encountered panic troops retreating from the British. The British were within minutes of overtaking the American troops. General Washington rallied what troops he had, and mounted a counter assault on the British. His action gave time for the rest of the Continental Army to arrive and join the battle.
The fighting went back and forth on a hot and humid day, neither side gaining an advantage. As dusk fell, General Washington had fresh troops to resume the attack which would have to wait until the following morning. However, the British did not give the Americans a chance to renew the fight. They slipped away under the cover of darkness and resumed their withdrawal to New York City.
The Battle of Monmouth resulted in the court martialing of Major General Charles Lee. It was also the last battle in the Revolutionary War fought between the two main armies.