The first USCGC Triton was a 165-foot cutter which operated out of United States Coast Guard Base 15 at Biloxi, Mississippi during what was referred to at the time as "the Prohibition War" -- operations against alcohol smugglers during Prohibition.
The fifth USS Triton (SSRN/SSN-586), a nuclear-powered radar picket submarine, was the first vessel to execute a submerged circumnavigation of the Earth.