7. The first ironclad warship to engage in combat was the CSS Virginia
After capturing the Gosport Navy Yard at Norfolk, Virginia, the Confederates worked speedily to rebuild the USS Merrimac as an ironclad warship. Renaming the vessel the CSS Virginia, the Confederate Navy hoped the ship would break the tightening blockade imposed by the United States Navy and its wood-hulled warships. It nearly did. Virginia destroyed USS Cumberland, forced USS Congress to surrender, and drove USS Minnesota aground in a single afternoon, seemingly impervious to enemy gunfire. The next day, Virginia returned to the scene to complete the destruction of the US fleet, only to encounter USS Monitor. The famous Battle of Hampton Roads was the first in which ironclad warships fought each other. But the previous day’s action was not the first time an ironclad warship engaged in battle, as is often reported.
At the end of January 1862, the US Army held in its inventory seven ironclad gunboats, designed by James Buchanan Eads. Built mostly in St. Louis, the gunboats were designed to support Army operations on the Mississippi River and its navigable tributaries. On February 6, 1862, these gunboats braved a minefield (called torpedoes at the time) and bombarded Fort Henry on the Tennessee River. The boats forced the fort to surrender after a bombardment of over an hour and a quarter. The boats endured heavy return fire from the fort’s artillery, suffering some damage. It was the first recorded use of ironclad warships in combat, preceding the Battle of Hampton Roads by just over a month. Eads gunboats served on the inland rivers and even the Gulf of Mexico throughout the war. They were a critical component of the successful siege of Vicksburg in 1863.