Jonathan Thorn (8 January 1779 – 15 June 1811) was an officer of the United States Navy in the early 19th century. He was born on 8 January 1779 at Schenectady, N.Y.. He was appointed a midshipman on 28 April 1800. Subsequently serving with the Navy during the Tripolitan War, Thorn volunteered to take part in the hazardous expedition to destroy the captured frigate Philadelphia, which lay beneath the guns of the defended Tripoli harbor. On 16 February 1804, Lieutenant Stephen Decatur, Jr., led a party of these volunteers in the ketch Intrepid into Tripoli and burned the erstwhile American frigate.
Attached to the schooner Enterprise, Thorn was then assigned to Gunboat No. 4, under Decatur's command. In this vessel, he participated in the attack on Tripoli, with Commodore Edward Preble's squadron on 3 August 1804. Specially commended by Decatur for his conduct in this battle, Thorn received command of one of the Tripolitan gunboats captured and commanded this vessel in the engagement with the Tripolitan pirates on 7 August.
Commissioned a lieutenant on 16 February 1807, Thorn became the first commandant of the New York Navy Yard at age 27. In 1810, he was granted a two-year furlough to command John Jacob Astor's sailing bark Tonquin in a voyage slated to take the ship to the Pacific Northwest to establish a fur trading post. Thorn arrived at the mouth of the Columbia River on March 22, 1811 and two days later and at the cost of eight lives, they crossed the bar. Thorn and his crew spent 65 days near the mouth of the river building Fort Astoria before part of the crew sailed back to the ocean. On June 5 they left the river and headed north to trade for furs. Thorn anchored off Clayoquot Sound, now in British Columbia around 15 June 1811, after a voyage which had taken the ship around Cape Horn to the Hawaiian Islands, to the mouth of the Columbia River and up the west side of Vancouver Island, Thorn soon attempted to trade with the local Nootka people. Angered by what they considered insulting behaviour, the Indians seized the Tonquin and, in a brief, bloody action, killed Thorn and his crew. The next day while the ship was being plundered by the Nootka, the vessel was blown up.
- Eddins, O. Ned. "John Jacob Astor - Pacific Fur Company: Astorians - Tonquin - Fort Astoria". Mountain Man Plains Indian Canadian Fur Trade. TheFurTrapper.com. Retrieved 2007-02-17.