New National, a wooden side-wheel steamer, was seized by Union Navy gunboats at Memphis, Tennessee, 6 June 1862, after they had destroyed the Confederate River Defense Fleet.

Placed in service as a transport, First Master A. M. Grant in command, for the U.S. War Department's Western Flotilla, New National carried troops in a joint expedition to St. Charles, Arkansas, where they landed 17 June, stormed Southern earthworks, and won control of the White River for the Union fleet.

Transferred from the War Department to the Navy 30 September 1862, New National served as a receiving ship and as a mail and supply boat for the Mississippi Squadron.

Returned to her owner, Pearson Montgomery, at the intervention of U.S. Secretary of the Treasury Salmon P. Chase, 21 March 1863, she was simultaneously chartered by the Navy and kept in service.

Following service maintaining Union communication and supply lines on the Mississippi River and its tributaries through the end of the Civil War, New National decommissioned at Mound City, Illinois, 12 April 1865 and was returned to her owner.