USS Isaac N. Seymour (1860) was a steamer acquired by the Union Navy during the American Civil War. She was used by the Navy to patrol navigable waterways of the Confederacy to prevent the South from trading with other countries. Isaac N. Seymour (also called Seymour, I. N. Seymour, and J. N. Seymour) was built at Keyport, New Jersey, in 1860 and was purchased by the Navy at New York from Mr. Schultz 26 October 1861.