 "Fearnot" was built by George W. Jackman Jr., Newburyport, Massachusetts; purchased by the Union Navy 20 July 1861; and commissioned 28 August 1861, Acting Master E. H. Faucon in command.From the time of her arrival at Key West, Florida, 17 September 1861, "Fearnot" served as coal and supply ship for the West Gulf Blockading Squadron, sailing out of Key West, Florida, to Ship Island, and after its fall, New Orleans, Louisiana.Her last service, from October 1865 to May 1866, was in carrying surplus ordnance to Pensacola, Florida, and guarding the large amounts of ammunition accumulating there.