American Diver, also known as the Pioneer II, was a prototype submarine built for the Confederate States of America military. It was the first successor to the Pioneer. The Diver was invented and built by the same consortium that built the Pioneer in New Orleans. It was composed of Horace Lawson Hunley, James McClintock, and Baxter Watson. They were forced to move their operations to Mobile, Alabama following the capture of New Orleans by Union forces in April 1862. Although ultimately unsuccessful, it served as a model in the development of the consortium's next submarine, the H. L. Hunley. The Hunley eventually became the first combat submarine to sink an enemy warship.