James R. McClintock, with Horace Lawson Hunley and Baxter Watson, built the submarine Pioneer at New Orleans in 1861 to defend the city against Federal forces. The three men later constructed two submarines at Mobile, Alabama, the second of which was named H.L. Hunley. This vessel was taken to Charleston, South Carolina, in August 1863. On 17 February 1864, after two fatal accidents, the refurbished H.L. Hunley became the first submarine to successfully attack an enemy warship when she sank USS Housatonic off Charleston.