American Revolutionary War: Fort Clinton and Fort Montgomery were captured by British forces under Sir Henry Clinton, dismantling the Hudson River Chains.

The American Revolutionary War, also known as the Revolutionary War or American War of Independence, was the armed conflict that comprised the final eight years of the broader American Revolution, in which American Patriot forces organized as the Continental Army and commanded by George Washington defeated the British Army. The conflict was fought in North America, the Caribbean, and the Atlantic Ocean. The war's outcome seemed uncertain for most of the war. But Washington and the Continental Army's decisive victory in the Siege of Yorktown in 1781 led King George III and the Kingdom of Great Britain to negotiate an end to the war in the Treaty of Paris two years later, in 1783, in which the British monarchy acknowledged the independence of the Thirteen Colonies, leading to the establishment of the United States as an independent and sovereign nation.

Fort Clinton was an American Revolutionary War fort erected by the Continental Army on the west bank of the Hudson River in 1776.

Fort Montgomery was a fortification built on the west bank of the Hudson River in Highlands, New York by the Continental Army during the American Revolution. Erected in 1776, Fort Montgomery was one of the first major investments by the Americans in strategic construction projects.

The Battle of Forts Clinton and Montgomery was an American Revolutionary War battle fought in the Hudson Highlands of the Hudson River valley, not far from West Point, on October 6, 1777. British forces under the command of General Sir Henry Clinton captured Fort Clinton and Fort Montgomery and then dismantled the first iteration of the Hudson River Chains. The purpose of the attack was to create a diversion to draw American troops from the army of General Horatio Gates, whose army was opposing British General John Burgoyne's attempt to gain control of the Hudson.