Hercules Mulligan not only had one of the Revolutionary War’s greatest names, this cunning haberdasher was also one of its best spies.

A year ago, even most American history professors probably had never heard of Hercules Mulligan, the American patriot whose name sounds like a punchline.

Thanks to the musical blockbuster Hamilton, Mulligan finally is famous, 190 years after his death. Of course, the real Mulligan was not quite what Lin Manuel Miranda’s casting director sought: “Ethnically Ambiguous / Mixed Race, African Descent… able to sing and rap well … the life of the party, dripping with swagger, streetwise and hilarious…. Joins the revolution to get out of being a tailor’s apprentice.”

Hercules Mulligan was a discrete but silver-tongued Irish immigrant in New York City, who prospered as a haberdasher, tailoring garments for colonial aristocrats and British officers. He was also a member of the Sons of Liberty, and his passion helped recruitAlexander Hamilton to the Revolutionary cause. His work also happened to make him a great, meaning oft-overlooked, spy.

This Mulligan mulligan—his second crack at fame—proves Gil Troy’s Law of Academic Insignificance: one popular hit upstages thousands of scholarly tomes. Think how Oliver Stone’s lies about JFK’s assassination eclipsed all of my historian colleagues’ truths or how Selma muddied LBJ’s civil rights reputation. And consider how many student term papers about the 1960s Mad Men has shaped. But one shouldn’t be too stuffy or self-pitying. Hamilton has introduced many to Revolutionary America’s creative hullabaloo, while resurrecting an important, underappreciated Founding Father.

The Irish-born Mulligan arrived in New York City when he was six in 1746—about to become yet another success story in our nation of immigrants. A graduate of King’s College—renamed Columbia University in 1784 after the rebellion against the monarch—the beefy, gregarious, newcomer prospered. He opened a tailor shop and married up, to Elizabeth Sanders, a British admiral’s niece. In 1765 Mulligan was among the first colonists to join the secret underground group, the Sons of Liberty. The benign British rule was turning oppressive, as a bankrupt mother country tried exploiting its colonies with taxes and other burdens. In 1770, Mulligan helped mob British soldiers who had been distributing leaflets denouncing the patriots in “The Battle of Golden Hill.” Three years later, Mulligan met Hamilton, a penniless orphan seventeen years younger, who had just arrived from the island of Nevis with a letter of introduction to Mulligan’s brother Hugh.

When Hamilton first enrolled in King’s College, he lived with Mulligan, who railed regularly about British imperial insults. Decades later, Mulligan would remember how his young friend “used in the evening to sit with my family and my brothers family and write dogrel rhymes for their amusement; he was allways amiable and cheerful and extremely attentive to his books. [sic].” Nevertheless, Mulligan’s anger was contagious. Hamilton eventually joined the Sons of Liberty too and in February 1775, the 18-year-old newcomer wrote a popular essay denouncing his new enemies, the British.

As the violence intensified, to maintain his business, understanding that a good tailor like a good barber should be a good listener, Mulligan avoided talking politics with his fancy British-oriented clients. Mulligan’s discretion helped him survive the British occupation of New York, which began in 1776—and ultimately gave him the opportunity to save George Washington’s life.

In 1779, some sources claim, a British officer insisted late one night he needed a warm “watch coat.” When Mulligan casually asked why the rush, the officer described his important mission, exulting, “before another day, we’ll have the rebel general in our hands.” Mulligan immediately mobilized his slave Cato, who was known to many of the well-outfitted British officers surrounding the city. Cato passed the information to Hamilton, who had become Washington’s aide de camp. Washington avoided the British ambush. Thus Hamilton’s hip hop Mulligan can rap: “A tailor spyin’ on the British government! I take their measurements, information, and then I smuggle it.”

Mulligan and Cato were already reliable sources for Washington regarding troop movements—working despite at least two interrogations by wary British officers. Mulligan occasionally collaborated with the New York-based Culper Ring and with the famous Jewish patriot Haym Solomon, whose German fluency made him a popular translator for the Hessian troops—and thus a great source of intelligence regarding troop movements.

In 1781, two years after the first Washington save, and a year after Benedict Arnold’s betrayal compelled Hercules Mulligan to charm his way out of jail, Hugh Mulligan’s import-export firm received a big rush order. Three hundred cavalrymen planning to capture General Washington in New London, Connecticut, needed supplies. Hercules Mulligan conveyed the information and Washington dodged the British again.

When the Revolutionaries won, Mulligan, who looked like all the other wealthy New York Loyalists, feared tarring and feathering or some other act of patriotic revenge. But George Washington remembered his “confidential correspondent.” On November 26, 1783, Washington led an “Evacuation Day” parade celebrating his return to New York. The triumphant general stopped at 23 Queen Street—today 218 Pearl Street—dismounted and ate breakfast with Mulligan. Pronouncing his savior “a true friend of liberty,” Washington generously ordered a full civilian wardrobe too. Mulligan hung a sign outside his shop: “Clothier to Genl. Washington.”

We have much to learn about and from Hercules Mulligan, migrant to the colonies, tailor to the aristocrats, mentor to Hamilton, confidante to Washington, traitor to our oppressors, Son of Liberty, and inspiration to democrats everywhere.