When the Civil War broke out, neither side were prepared for naval battles on the western rivers. The inevitable result was an urgent and innovative period of warship experimentation.
Before the war, James Buchanan Eads (1820-1887), an inventive self-taught engineer living in St. Louis and familiar with the Mississippi River, proposed that the U.S. government invest in the development of steam-powered, ironclad warships. He had recognised that the emerging conflict would, in large part, focus on the control of the country’s river systems. His idea was cooly recieved. But when hostilities began, he was summoned to offer the U.S. government advice on how to wrest control of the lower Mississippi River from the Confederacy.
Eads proposed building seven armor-plated, shallow-draft gunboats to assist the Union Army against Confederate fortifications protecting their supply lines downriver. He was awarded a contract, and in a remarkable feat, completed his monumental task in less than one hundred days. The CAIRO, CARONDELET, CINCINNATI, LOUISVILLE, MOUND CITY, PITTSBURG, and ST. LOUIS, collectively known as City Class Ironclads, were commissioned and in service on the western waters by January 1862.
These gunboats were the first ironclads built in the United States. Heavily armored and mounted with heavy rifled guns capable of piercing the thickest Confederate armor, they formed the backbone of the Union’s river forces. James Eads also converted commercial steamers into ironclads at St. Louis shipyards, by reconfiguring them with the sloped armored superstructure that characterized his purpose-built ironclads. Though slower and less heavily armed than the City Class vessels, the were successful additions to the Union’s “Western Flotilla.”
The ironclad idea would be adopted by the Confederacy and both sides would improve on James Ead’s original design throughout the war. At the outset, the Confederate Navy only a handful of ships, most of which were old, wooden river steamers lightly built for commercial purposes. Lacking the material, engineering and financial resources of the North, the South would need to seize, buy, capture or build a fleet as quickly as possible. To this end, the Confederacy assembled whatever vessels could be obtained or built at major ports, including a variety of small wooden vessels, and locally-built ironclads.
The Confederate War Department established a “River Defense Fleet” in 1861, based in New Orleans. It consisted of fourteen commercial riverboats converted into rams by adding heavy, sharp timbers to their bows and stacking cotton bales on their decks as a form of armor, resulting in the term “cottonclad”. In addition, some twenty-five other Confederate steamboats with artillery mounted on their decks, making them gunboats, were operating elsewhere on the Mississippi and its tributaries. The South was able to overcome its deficiencies with some remarkable innovations that nearly turned the tide several times during the Civil War. By the second year of the war, however, it became obvious that superior warships were not within the South’s means.
In 1861, the Confederate Navy began building six more ironclad gunboats and converted yet another steamboat. However, this growing river force suffered disaster in two full-scale naval battles in 1862. The battles of New Orleans and Memphis broke the Confederate Navy’s control of the lower Mississippi River. So much so, that during the Vicksburg campaign, there were no Confederate ironclads and only a handful of gunboats on the western rivers.
Approximately thirty-three Union Navy vessels participated in the Vicksburg campaign at various times: thirteen ironclads, seven rams, eleven light draughts or “tinclads”, and two “timberclads.” This Union naval force began its existence as an Army force known as the Western Flotilla.
Admiral David G. Farragut’s Naval Forces in conjunction with General Ulysses S. Grant’s Army of the Tennessee captured the city of Vicksburg after a siege that lasted from May 18 to July 4, 1863. The surrender of Port Hudson followed on July 9. The Union’s control of the Mississippi was assured, effectively dividing the Confederate States.