Great Chain

The Hudson River Chain refers to two chain booms and two chevaux de frise constructed from 1776 to 1778 during the American Revolutionary War across the Hudson River as defenses to prevent British naval vessels from sailing upriver. These defenses along the Hudson River were overseen by the Highlands Department of the Continental Army. The most significant and successful was the Great Chain, constructed from West Point in 1778, and used through 1782 after the war's end. The huge links for the chains were forged at iron works in Orange County, New York.

Both the Americans and British knew that passage on the Hudson River was strategically important to the war effort. Americans worked to devise plans to slow or block ship passage on the river, planning to attack enemy ships by cannons and mortar located at existing defensive forts or those to be constructed.

In late 1776 Henry Wisner, a resident of Goshen, NY and one of New York's representatives to the Continental Congress, along with Gilbert Livingston, sounded the Hudson River and, as part of a Secret Committee of the "Committee of Safety", recommended the placement of chains in strategic locations along the Hudson.

The Americans eventually constructed such obstacles across the river at northern Manhattan, between forts Washington and Lee in 1776; at the newly constructed Fort Montgomery on the West Bank on Popolopen Creek in 1776–1777 south of West Point; a partially completed one at Pollepel Island in 1776–1777 north of West Point; and the Great Chain (1778–1782) between West Point and Constitution Island. The largest and most important project was the latter chain at West Point, which was reset each spring until the end of the war. Attention was concentrated on the West Point area because the river narrowed there, and curved so sharply that, together with winds, tides and current, ships already had to slow to navigate the passage. Creating more obstructions on the river enabled the shore batteries to work their cannons against the enemy.

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