American Privateer. Born in County Donegal, Ireland, as a youth he traveled to the American Colonies and was apprenticed on a ship in the West Indian trade. At the time of the American Revolution, he made his way to France and obtained a commission in the American Navy and letter of marque dated March 1, 1777 from the American commissioners. He sailed from Dunkirk in May as captain a 10 gun lugger, Surprise. Surprise shortly returned with two prizes, one of them an British mail packet. The British were livid and protested to the French government calling Conyngham a pirate. They demanded the arrest of the ‘Dunkirk Pirate' and the return of the packet. The Surprise was seized, her captain and most of his crew were put in prison. Conyngham's commission was confiscated and was never returned to him. Benjamin Franklin and Silas Deane procured an order for the release of Conyngham and his crew, and provided him a new ship. The vessel was a 14 gun cutter called Revenge. Conyngham was issued a new commission and sailed in July of 1777. For two months Revenge remained at sea cruising off north-western Europe and the British Isles, word of the cutter's great success embarrassed the British, sent London insurance rates skyrocketing, and inhibited British trade. The Admiralty ordered their warships to find and destroy her. Conyngham made several cruises from Spanish ports and captured numerous prizes. At one point he passed the Strait of Gibraltar and operated in the Mediterranean. As Revenge's fame spread, British diplomatic pressure was brought to bear on the Spanish to bar her from Spanish ports. Conyngham sailed for the West Indies in September 1778. Revenge scooped up another 60 enemy vessels along the way. Revenge arrived in Philadelphia in February 1779, laden with arms and munitions for the Continental Army. Revenge sailed again in April 1779. She was captured almost immediately off the New York coast by the British Man o' War, Galatea. According to Conyngham, a British officer confiscated his commission and confined him to the hold. He was then transported to England in irons accused of piracy. Benjamin Franklin worked to prevent Conyngham's execution as a pirate, and to upgrade his status to prisoner of war. Conyngham was installed at Mill Prison in Plymouth, where he made no less than three escape attempts. He finally escaped with about fifty others in December of 1779. He then found his way to Holland. He was recaptured while attempting to return to America in 1780. A year passed before he was included in a prisoner exchange. Upon his release, he immediately headed for France where he was preparing a vessel when the war ended. After the war, he returned to the merchant service. When he was well into his sixties he was a member of the Common Council of Philadelphia, and assisted in the defense of that city during the War of 1812.