A historic plaque at the Monmouth Battlefield contains the following description: 
"The Battle of Monmouth was a turning point in the American Revolutionary War. In 1776 and 1777, the British Army had repeatedly defeated the main Continental Army. By the beginning of 1778, General George Washington and the Continental Army desperately needed a victory.
"On June 18th, concerned that the French might block the Delaware River, the British abandoned Philadelphia and began marching their army of 20,000 British, German, and Loyalist troops across New Jersey to their main base in New York City. On June 19th, Washington and 13,00 men, fresh from Von Steuben's military training at Valley Forge, set out to intercept the Crown forces.
"The Battle began at about 10 AM [on June 28th], two miles east of here at Monmouth Courthouse and continued for over seven hours, making it one of the longest battles of the Revolution. By 5:30 PM, the British had retreated and the firing ceased. At dawn on the following day, Washington moved fresh troops forward to resume the battle, but the British forces had slipped away during the night to continue their journey to New York City.
"The Battle of Monmouth was a political triumph for the Continental Army and General Washington. The Continental Army met the British in open field, held their own and forced them to retreat. It was their first victory in two years."