USS Worcester was a Contoocook-class bark-rigged screw steam sloop-of-war in the United States Navy. Built as Manitou of unseasoned white oak timbers, she was laid down in 1863 at Boston, Massachusetts, by the Boston Navy Yard and launched on 25 August 1866. Renamed Worcester on 15 May 1869, she was apparently placed in commission on 27 February 1871, Commander William D. Whiting in command. Among the ship's officers at the time of her commissioning was the naval strategist and author, Lieutenant Commander Alfred T. Mahan.