Historian James McPherson talked about his book, War on the Water: The Union and Confederate Navies, 1861-1865, which presents a history of the use of naval forces by the Union and Confederate armies during the Civil War. He examined the impact that each navy made during the War, Union naval support of numerous battles including Vicksburg and New Orleans, the Confederate’s use of naval mines, and the deployment of a submarine. James McPherson spoke with historians Craig Symonds and Harold Holzer at the New York Historical Society in New York City and responded to questions from the audience.