The USS Proteus (AC-9) was a lead ship of her class of four colliers, constructed to serve the United States Navy. Laid down on October 31, 1911, by Newport News Shipbuilding and Dry Dock Company, she was launched on September 14, 1912, and commissioned on July 9, 1913. The vessel’s design was typical of early 20th-century colliers, built to transport coal and later oil to support naval operations. Proteus's early service involved multiple supply runs along the U.S. East Coast, including four voyages to Veracruz, Mexico, to refuel battleships and cruisers of the Atlantic Fleet. In December 1914, she carried men, fuel, and stores to the Philippines, completing her final such run in August of that year. Her operational range extended across the Atlantic and into South America, supplying coal, oil, personnel, and provisions to ships at Rio de Janeiro and Montevideo, as well as operating between Norfolk, Boston, and New York City under the Naval Overseas Transport Service. During World War I, Proteus sailed to the British Isles and Brest, France, transporting coal and supplies, notably shipping coal from Welsh ports to France. Post-war, her duties included replenishing the U.S. Fleet in the Caribbean and delivering fuel to Pearl Harbor in 1920 and Callao, Peru, in 1921. Her last Caribbean supply run concluded in April 1923, after which she operated mainly between Norfolk and Melville, Rhode Island. Decommissioned in March 1924, Proteus remained inactive until her name was struck from the Naval Vessel Register in December 1940. She was sold to Saguenay Terminals Ltd. in Montreal in March 1941 and operated as a merchant vessel in the Canadian Merchant Navy. Tragically, she was lost at sea sometime after November 23, 1941, with her fate remaining uncertain. Possibly lost in the Caribbean Sea, her disappearance remains shrouded in mystery, with no confirmed U-boat engagement or cause. Proteus’s loss echoes the tragic fate of her sister ships Cyclops and Nereus, both of which also vanished without trace in the Caribbean area during wartime.

This description has been generated using GPT-4.1-NANO based on the Vessel's wikidata information and then modified by ShipIndex.org staff.