1. Nathan Hale

Hale was undoubtedly courageous, but according to most historians, he wasn’t a very skilled intelligence officer. It only took a few days before his suspicious questions drew the attention of loyalist locals, and he later blew his cover after a British agent approached him in a tavern and pretended to be a fellow Patriot spy. Hale was arrested the next day and discovered to have incriminating documents concealed beneath the soles of his shoes. Charged as an illegal combatant, he was executed by hanging on the morning of September 22. Accounts of Hale's final words vary, but according to written reports and popular legend, the 21-year-old patriot faced the gallows “with great composure and resolution” before uttering the famous words, “I only regret that I have but one life to give for my country.”

Often dubbed “America’s first spy,” Nathan Hale was a Yale graduate who served in Knowlton’s Rangers, a short-lived Continental reconnaissance unit. When General George Washington’s forces became bottled up on Manhattan Island in September 1776, Hale volunteered for a mission to gather much-needed intelligence behind enemy lines. He was ferried across the Long Island Sound on September 16, slipped into the occupied town of Huntington and began surveying British fortifications and encampments while posing as a schoolmaster.

2. James Armistead

James Armistead Lafayette (R) at Yorktown, standing with Marquis de La Fayette (L).

During the Yorktown campaign, the Marquis de Lafayette found an unlikely secret agent in James Armistead, a black slave who got his master’s permission to assist the Continental Army. The Virginia-born bondsman began his service by transporting dispatches and intelligence reports across enemy lines. He then graduated to full-blown espionage in the summer of 1781, when he infiltrated Charles Cornwallis’s camp by posing as a runaway slave loyal to the British. He proved so convincing in the undercover role, that Cornwallis eventually enlisted him to work as a British spy. Armistead agreed and immediately began funneling the Redcoats' phony information supplied by Lafayette, including a fraudulent report that referenced nonexistent units of Continental troops. He also kept his ears open for any word of enemy movements. In July 1781, he was one of the first sources to inform Lafayette that the British were marshaling their forces at Yorktown.

Despite having risked his life for his country’s freedom, Armistead was sent back to his master after the war and held as a slave for several more years. He finally won his release papers in 1787, thanks in part to Lafayette, who wrote a letter to the Virginia legislature on his behalf. As a sign of his gratitude to his former commander, Armistead later changed his name to James Armistead Lafayette.

3. Benjamin Tallmadge and the Culper Ring

Serving with distinction at the Battles of White Plains, Brandywine, and Germantown, Continental dragoon Benjamin Tallmadge was also the mastermind behind the Culper Spy Ring, one of the most effective espionage networks of the American Revolution. The New York native first organized the cabal in late 1778 at the behest of General George Washington. Operating under the pseudonym John Bolton, he recruited childhood friend Abraham Woodhull and several other acquaintances to provide intelligence from in and around British-controlled Long Island. Tallmadge instructed his operatives to communicate via a complex system of dead drops and coded messages. He even had them write some of their reports in invisible ink that could only be read after being brushed with a chemical compound. Once smuggled out of the city, the documents would be ferried to Tallmadge’s coastal Connecticut headquarters by a fleet of whaleboats operated by an agent named Caleb Brewster.

Despite operating from the heart of enemy territory, Tallmadge’s Culper Ring managed to gather intelligence for some five years without losing a single agent to the British. One of their most significant achievements came during the summer of 1780 when they informed Washington of a British plan to ambush French forces gathered at Newport, Rhode Island.

4. Enoch Crosby

French map of the Hudson River Valley and surrounding area, New York, 1778. (Credit: Buyenlarge/Getty Images)
Getty Images / Buyenlarge
French map of the Hudson River Valley and surrounding area, New York, 1778.

Enoch Crosby’s spy career began with a simple case of mistaken identity. In 1776, the Connecticut-born shoemaker was making his way to a Continental Army camp in New York when he was confused for a British sympathizer and invited to a meeting of loyalist militiamen. Crosby played along and later reported what he learned to Patriot leader John Jay, who seized the opportunity to recruit him as one of the nation’s first counterintelligence operatives. The job required Crosby to work deep undercover. To help sell his new identity, his handlers arranged for him to be arrested as a loyalist before staging his escape to the Hudson River Valley. Crosby then reunited with the British sympathizers and began reporting on their movements. Thanks to the intelligence he gathered, the entire gang was rounded up in a Continental raid a few days later.

In the months that followed, Crosby infiltrated British loyalist groups on at least four more occasions. Each time he would be “arrested” along with his hapless co-conspirators, only to later escape and return to the field to start the whole process over again. The young spy carried a special pass that would identify him as an American agent in a pinch—he once had to use it to avoid being picked up by Continental sentries—but outside of Jay and a few others, no one knew he was actually working for the colonials. Before he was finally discharged and hailed as a hero in 1777, even Crosby’s own parents believed their son was a traitor to the Patriot cause.

5. Lewis Costigin

British-Hessian troops under the command of General Howe parading through New York as they took over the city during the American War of Independence. (Credit: MPI/Getty Images)
Getty Images / MPI
British-Hessian troops under the command of General Howe parading through New York as they took over the city during the American War of Independence.

Not only did Lieutenant Lewis Costigin supply valuable intelligence from behind British lines, he did it while openly wearing a Continental Army uniform. His bizarre career in espionage began in early 1777 when George Washington sent him to New Brunswick, New Jersey to report on British movements after the Battle of Trenton. Costigin was promptly captured, but he was wearing enough of a uniform at the time to be classified as a soldier rather than a spy, thereby avoiding the noose. After shipping him to New York City as a prisoner of war, the British placed him on parole and allowed him to wander the city freely on a pledge that he wouldn’t take up arms or communicate with his superiors.

Costigin was exchanged for a British officer in September 1778, but rather than return to his unit, he remained in occupied New York and began collecting intelligence for the Continentals—which he was now legally free to do under the terms of his parole. Luckily for Costigin, the British had grown so used to seeing him around town they no longer viewed him as a threat. Though still clad in an enemy uniform, he was able to openly roam the streets gathering information on everything from troop movements to military shipping and British army rations, all of which he reported to Washington in dispatches written under the pseudonym “Z.” By the time Costigin finally left New York in January 1779, he had spent some four months spying on the British in plain sight.

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