Information during the Revolutionary War was passed along using handwritten letters. Spies used various methods to protect their messages in case they were intercepted by the enemy. These methods included invisible ink, secret codes, and mask letters.
Invisible Ink - The Americans used an invisible ink called a "stain" that was developed by Doctor James Jay. It took a special chemical (known only to the Americans) to reveal the writing.
Secret Codes - Secret codes were also used in combination with a cipher to keep messages safe. In many cases, however, the enemy was able to decipher the codes.
Mask Letters - A final way to hide a message used a specific mask on what seemed to be a normal letter. The mask would reveal a secret message hidden within the letter.
Spy Nathan Hale is Captured Source: CIA
Disguises and Covers
Spies often used covers and disguises to get the enemy to trust them. They would pretend to be peddlers or local farmers. Loyalists would pretend to be patriots to get into groups like the Sons of Liberty. Patriots would do the same thing to find out what the loyalists were doing.
Culper Spy Ring
One of the largest spy operations of the Revolutionary War was the Culper Spy Ring. The ring was organized by George Washington's spymaster Benjamin Tallmadge. The goal of the ring was to provide Washington with information about the British army in New York City. The two main secret agents in the ring were Abraham Woodhull and Robert Townshend.
The Culper Spy Ring provided lots of valuable information to George Washington including British troop movements, strategic plans, and that American officer Benedict Arnold was going to turn traitor.
Benjamin Tallmadge by Ezra Ames
Nathan Hale - Hale was an American spy who was caught while gathering information in New York City. He was hung by the British, but is remembered for his famous last words which were "I only regret that I have but one life to give for my country."
Benjamin Tallmadge - Tallmadge ran the American spy network under George Washington. He organized the famous Culper Spy Ring in New York City.
Abraham Woodhull - Abraham was a key member of the Culper Spy Ring. He used the alias Samuel Culper when sending messages and working as a spy.
Lydia Darragh - Lydia spied on British officers who met in her home to discuss battle plans. She then passed on the information to American soldiers.
Benedict Arnold by Henry Bryan Hall
Benedict Arnold - Benedict Arnold was a general with the Continental Army when he decided to switch sides. He planned to turn over Fort West Point to the British before his plans were exposed and he fled to the British.
Hercules Mulligan - Mulligan owned a clothing store in New York City where many British officers shopped. He would gather information by talking to the officers and then pass it on to George Washington.
Daniel Bissell - Bissell pretended to desert the Continental Army and join the British. He worked for the British for over a year, gathering all sorts of detailed information.
Nancy Hart - There are many stories about the exploits of Nancy Hart during the war. They include her dressing up as a man to infiltrate British camps as well as capturing a number of British soldiers in her house.
Interesting Facts about Revolutionary War Spies
Nancy Hart by Unknown
The Culper Spy Ring had one female agent known only by her code name "355."
The army had its own intelligence unit headed up by Thomas Knowlton. The group became known as Knowlton's Rangers.
The punishment for captured spies was usually death.
The Committee of Secret Correspondence was in charge of foreign intelligence. Benjamin Franklin was an original member of the committee.
The TV series Turn is about the Culper Spy Ring in New York City.