No less an authority than the American Revolution historian Thomas Fleming calls Dr. Benjamin Samuel Church Jr. “the least known and most dangerous spy in American history.”
Surely he was in a position to do grave harm to the fight for independence from the British. As John Nagy writes, Church was “one of the most admired and respected patriots in Massachusetts,” on a par with John and Samuel Adams and John Hitchcock. He served “on almost every committee of importance” and was the on-site political leader in the state.
In terms of position, Church inarguably was the most important American spy ever, for his treachery could have led to the loss of the war that created the United States. By comparison, such spies as Alger Hiss of the State Department, Aldrich Ames of the CIA and Robert Hanssen of the FBI were mere spear-carriers.
So renowned was Church as a physician that the Continental Congress, meeting in Philadelphia in June 1775, appointed him director of the first American army hospital in Cambridge, Mass. The position “gave him unlimited access to American military facilities and knowledge of the readiness of American forces.” Much of his value as a spy for the British stemmed from this appointment.
At first blush, Church seemed the archetypal American revolutionary. Born into a politically active Boston family, Church studied medicine at Harvard and then in London, where he married a British woman.
As a young man, he achieved some fame as a prolific writer of poetry and satire while pursuing a medical career. His most prominent public performance as a rebel came when he was chosen to deliver the oration at a memorial service for victims of the notorious Boston Massacre.
Church’s other activities seemed suspicious, especially his close association with two Loyalists, a retired English captain and a customs commissioner. Church replied that he was trying to find their views on new taxes. Perhaps. Mr. Nagy suggests they could have been couriers for intelligence reports to the British.
The author posits that Church turned traitor because of money. He spent lavishly, building an expensive summer home, then a house in “an upscale section of Boston filled with the elegant homes of the rich.” He appealed to the royal governor, Thomas Hutchinson, for money for a maritime hospital.
Did funds change hands? Mr. Nagy quotes a letter written by Hutchinson in January 1772, “the Doctor Church is now a writer on the side of Government.” Hutchinson also indicated that Church was paid for writing anonymous papers for the government. He seemed to have a steady supply of British gold coin.
Meanwhile, through Gen. George Washington’s counterintelligence officers, the rebels came to suspect that the British governor general, Thomas Gage, was privy to secrets from their camp, including near-verbatim reports of what was said at meetings of an intelligence cell at the Green Tavern.
At the time, nothing pointed to Church, but papers found years later in Gage’s files — most of them labeled “intelligence” — revealed the vast scope of Church’s spying. In letters to Gage, Church repeatedly expressed his loyalty to the Crown, all the while publicly posturing as an enthusiastic revolutionary patriot. “May I never see the day when I shall not dare to call myself a British American,” he wrote in one letter to Gage.
Church’s downfall came when he entrusted a letter to his pregnant mistress, Mary Wenwood (a sometime prostitute, as well) for delivery to a British officer. Not the most intelligent of women, Wenwood unwisely asked her former husband to help her find the officer. When he saw that the letter was written in cipher, he became alarmed, and in due course it was forwarded up the rebel chain of command to Washington.
A cryptographer quickly deciphered the letter, which contained “intelligence of a black and treacherous nature,” details on rebel recruitment and supplies (noting, for instance, that “twenty tons of powder are now in camp”).
Washington brought Wenwood in for questioning. As he wrote to Congress, “For a long time she was proof against every threat and persuasion to discover the author.” However, after four hours, during which “she was terrified by the threats of severe punishment she was brought to confession.” She named Church as the author, and he was quickly arrested.
Brought before a military council, Church admitted writing the letter, but he claimed he was innocent, “that he was trying to impress the enemy of the size of the American army, when it was in great need of ammunition in order to prevent an attack.” He failed. The council voted unanimously that Church “had carried on a criminal correspondence.”
The news of Church’s treachery stunned friends. John Adams scorned a man “who grossly violates the principles of morals.” He and others feared the treachery could demoralize the revolution. James Warren denounced Church for “having formed an infamous connection, with an infamous hussy to the disgrace of his own reputation, and probable ruin of his family.”
Because of confused language in the articles of war concerning punishment, Washington chose to let the Massachusetts House of Representatives decide what to do with Church. Once again, he professed innocence. Once again, he was convicted, in November 1775. The House voted to hold him in close confinement indefinitely.
After protracted negotiations, a deal was struck in 1778 to exchange Church for Dr. James McHenry, a surgeon held by the British. In February, he boarded the sloop Welcome for transport to British custody on the island now known as Martinique. The ship vanished at sea, and naught was heard of Church again.
His wife went to England, where she claimed a pension on the grounds “that her husband was a spy.” The Crown granted her 150 pounds a year, later reduced to 100 pounds.
Mr. Nagy, a professor at St. Francis University in Pennsylvania, has produced a valuable source book on intelligence during the American Revolution and a good read.
Joseph C. Goulden is the author of 18 nonfiction books.