Battle of the Ironclads
In early March 1862, the fledgling navy of the Confederate States of America attempted to break the U.S. Navy's blockade in the Hampton Roads of Virginia, at the confluence of the James, York, Elizabeth and Nansemond Rivers. The Commonwealth of Virginia had seceded from the Union less than a year prior (on April 17, 1861), though parts of the Commonwealth remained in Union control (e.g., the western counties -- soon to become the state of West Virginia -- and Fortress Monroe, at the tip of the Virginia Peninsula).
The U.S. Navy retained command of the seas, and imposed a naval blockade on the CSA to restrict their trade -- and their ability to generate revenues to sustain their secession. While northern states were the most populous (shown by Lincoln's victory in the 1860 presidential election -- despite winning zero electors from Southern states or from New Jersey) and most heavily industrialized (with 80% of total U.S. manufacturing capacity and 67% of U.S. rail lines), nearly 50% of America's GDP in the mid-19th century came from cotton. In fact, southern output of cotton was more than 80% of the entire world's production.
When the Commonwealth of Virginia seceded, the U.S. Navy vacated the oldest shipyard in the nation (Gosport Shipyard in Portsmouth, VA, on the Elizabeth River) and scuttled the steam frigate "USS MERRIMACK" in place. The Confederacy raised her and rebuilt her as an ironclad ram, rechristening her as "CSS VIRGINIA".
On the morning of March 8th, 1862, the VIRGINIA steamed into the Hampton Roads with the intention of breaking the Union blockade. Ramming USS CUMBERLAND below the waterline and then forcing the surrender of USS CONGRESS, VIRGINIA returned to port after darkness for repairs. The next morning, she returned to finish off the Union fleet -- but encountered a new arrival to the scene: USS MONITOR, the first true "ironclad" commissioned by the U.S. Navy.
Though the ensuing battle ended in a standoff, the event proved decisive for the Union -- which preserved the blockade's stranglehold on CSA trade.
Our home in Virginia was just a few miles south of the waters where the Battle of the Hampton Roads took place. As proof that to the victor goes the spoils, even south of the Mason-Dixon Line, U.S. Interstate 664 (the western edge of the Hampton Roads' "beltway") crosses the battle site via the Monitor-Merrimac Memorial Bridge-Tunnel (changing VIRGINIA back to its original U.S. Navy name -- albeit without the "k").