British forces occupied New York in August 1776, and the city would remain a British stronghold and a major naval base for the duration of the Revolutionary War. Though getting information from New York on British troop movements and other plans was critical to General George Washington, commander of the Continental Army, there was simply no reliable intelligence network that existed on the Patriot side at that time. That changed in 1778 when a young cavalry officer named Benjamin Tallmadge established a small group of trustworthy men and women from his hometown of Setauket, Long Island. Known as the Culper Spy Ring, Tallmadge’s homegrown network would become the most effective of any intelligence-gathering operation on either side during the Revolutionary War.

The Dangers of Spying

In mid-September 1776, the American officer Nathan Hale was hanged without trial in New York City. British authorities had caught Hale when he was on his way back to his regiment after having penetrated the British lines to gather information. Hale’s death illustrated the grave dangers inherent in spying for the rebels during the Revolutionary War, especially in the British stronghold of New York. Meanwhile, Benjamin Tallmadge, a young cavalry officer from Setauket, had enlisted in the Continental Army when the American Revolution began in 1775 and was soon awarded the rank of major. In mid-1778, General George Washington appointed Tallmadge the head of the Continental Army’s secret service; he was charged with establishing a permanent spy network that would operate behind enemy lines on Long Island.

Did you know? In addition to serving as head of Washington's secret service, Major Benjamin Tallmadge participated in many major battles fought by the Continental Army in the northern states. Fellow spy Caleb Brewster served under Tallmadge in the capture of Fort St. George at Mastic, New York in November 1780.

Tallmadge recruited only those whom he could absolutely trust, beginning with his childhood friend, the farmer Abraham Woodhull, and Caleb Brewster, whose main task during the Revolution was commanding a fleet of whaleboats against British and Tory shipping on Long Island Sound. Brewster, one of the most daring of the group, was also the only member whom the British had definitely identified as a spy. Tallmadge went by the code name John Bolton, while Woodhull went by the name of Samuel Culper.

Workings of the Culper Spy Ring

Woodhull, who began running the group’s day-to-day operations on Long Island, also personally traveled back and forth to New York collecting information and observing naval maneuvers there. He would evaluate reports and determine what information would be taken to Washington. Dispatches would then be given to Brewster, who would carry them across the Sound to Fairfield, Connecticut, and Tallmadge would then pass them on to Washington. Woodhull lived in constant anxiety of being discovered, and by the summer of 1779, he had recruited another man, the well-connected New York merchant Robert Townsend, to serve as the ring’s primary source in the city. Townsend wrote his reports as “Samuel Culper, Jr.” and Woodhull went by “Samuel Culper, Sr.”

Austin Roe, a tavernkeeper in Setauket who acted as a courier for the Culper ring traveled to Manhattan with the excuse of buying supplies for his business. A local Setauket woman and Woodhull’s neighbor, Anna Smith Strong, was also said to have aided in the spy ring’s activities. Her husband, the local Patriot judge Selah Strong, had been confined on the British prison ship HMS Jersey in 1778, and Anna Strong lived alone for much of the war. She reportedly used the laundry on her clothesline to leave signals regarding Brewster’s location for meetings with Woodhull.

Achievements of the Culper Spy Ring

Despite some strained relations within the group and constant pressure from Washington to send more information, the Culper Spy Ring achieved more than any other American or British intelligence network during the war. The information collected and passed on by the ring from 1778 to war’s end in 1783 concerned key British troop movements, fortifications and plans in New York and the surrounding region. Perhaps the group’s greatest achievement came in 1780 when it uncovered British plans to ambush the newly arrived French army in Rhode Island. Without the spy ring’s warnings to Washington, the Franco-American alliance may well have been damaged or destroyed by this surprise attack.

The Culper Spy Ring has also been credited with uncovering information involving the treasonous correspondence between Benedict Arnold and John Andre, chief intelligence officer under General Henry Clinton, commander of the British forces in New York, who were conspiring to give the British control over the army fort at West Point. Major Andre was captured and hanged as a spy in October 1780, on Washington’s orders.

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