Irish-born United States Navy Captain Gustavus Conyngham, “The Dunkirk Pirate,” is captured by the British Royal Navy in the waters off New York on April 27, 1779.

Conyngham is born in County Donegal in 1747 and emigrated to British America in 1763 in search of a better life. He settles in Philadelphia in order to work for his cousin Redmond Conyngham in the shipping industry. When the American Revolutionary War begins in 1775, he immediately sailed to France to try to procure supplies needed for the war effort.

The British become aware of Conyngham’s plans and manage to maneuver him out of his ship with the help of the Dutch. After the loss of his ship, he heads back to France, hoping to connect with an ally to the United States. It is there he meets Benjamin Franklin, who helps him in his adventures many times in the future. They form a lasting relationship, and Conyngham eventually awards Franklin the nickname “the Philosopher” for his intellectual fortitude and resourcefulness. Franklin is entrusted with several commissions of the Continental Navy, and on March 1, 1777, Conyngham is appointed Captain of the lugger Surprise.

Conyngham scores a first victory that would warm the heart of any Irishmen, capturing the British merchant ship Prince of Orange on May 3, 1777. Later that year he is commissioned a captain in the Continental Navy and given command of the USS Revenge. He begins a series of highly successful raids into British waters from the port of Dunkirk, thus earning his sobriquet “The Dunkirk Pirate.”

In 1778 Conyngham sets sail for the West Indies and terrorizes British vessels there before finally returning to Philadelphia on February 21, 1779. He and his men had claimed 60 prize vessels in just 18 months. When he sets sail again his luck runs out and his ship is captured by the British vessel HMS Galatea on April 27, 1779. Conyngham was taken to prison in England and treated harshly by his British captors.

After two failed escape attempts, Conyngham tunnels his way out of Mill Prison in Plymouth and manages to make his way to the continent. He joins John Paul Jones on a cruise on the Alliance before returning to the United States. He is captured by the British again in March 1780 and spends another year in Mill Prison.

After the war Conyngham fails in his efforts to continue his naval career or to gain recognition from the United States Congress for his service during the war. He had lost the commission papers given to him by colonial representatives in Paris in 1777. It is said that he assists in the defense of Philadelphia against his old British foes during the War of 1812.

Gustavus Conyngham dies in Philadelphia seven years later on November 27, 1819. Nearly a century later, John Sanford Barnes, a retired navy captain and naval historian, acquires a cache of autographs and documents from a sale by Charavay of Paris. In the collection is Conyngham’s commission from Benjamin Franklin. Barnes publishes his discovery in September 1902, proving that the “Dunkirk Pirate” had never been a pirate at all, but one of the first heroes of the United States Navy.

(Pictured: Captain Gustavus Conyngham, Continental Navy. Painting by V. Zveg, 1976, based on a miniature by Louis Marie Sicardi. Courtesy of the U.S. Navy Art Collection, Washington, D.C. U.S. Naval Historical Center Photograph.)