After the outbreak of the American Civil War, the Confederate States Navy purchased a number of vessels for military use. One of these was Lizzie Simmons, which was purchased on October 12, 1861, while at New Orleans. During January and February 1862, the vessel went through the process of conversion into a gunboat. The Confederates armed her with seven cannons, including an smoothbore of a model similar to the Paixhans gun and two 32-pounder (14.5 kilogram) rifled guns. Renamed to Pontchartrain, she was commissioned into Confederate service in March and placed under the command of First Lieutenant John W. Dunnington, who had previously served on the gunboats CSS McRae and CSS Tuscarora. After her commissioning, she was sent up the Mississippi River to support the Confederate defenses at Columbus, Kentucky.
