Blockades and Blockade Runners

By 1863, the Union blockade is really beginning to bite. The blockading fleet includes more new steamers, while both sides are racing to produce a new type of vessel with iron armor. The ironclad.

Some southern steamers manage to break through the blockade with an early-morning dash, when boilers on Federal warships have reduced steam pressure. But only the fastest make it to the safety of the open ocean.

Commerce raiders are different, as they don't need access to southern ports. Instead, they roam the high seas, attacking Union shipping of all kinds. The three most deadly raiders are built in England, and then remain at sea.
Union blockade, Civil War map

  Blockade Tightens
Over time, the Union blockade of southern ports is able to choke off 90% of southern exports, including their big money-maker, cotton. By the end of the war, 500 ships are involved in blockading duties, destroying or capturing 1,500 Confederate 'blockade runners,' which are their fastest steamers. The blockade also halts imports of food and war material.

Confederate commerce raiders, Civil War

  Fighting Back at Sea
While blockade runners are merchant vessels carrying cargo to and from Europe, commerce raiders are pure warships. The three that cause the most damage are all built in England, and sail the world's oceans without ever needing to enter southern ports. The Alabama is financed with cotton. The South also uses privateers, which are private vessels authorized to attack Union shipping. Maine, alone, loses 100 ships to southern raiders.


Monitor and Merrimack, 1863

  Iron Meets Iron
The famous 'battle of the ironclads' occurs early in the war. The Confederates manage to launch their vessel first, attacking vessels on Federal blockade duty. Built on the burned-out hull of an abandoned Federal frigate called the Merrimack, she is re-named the Virginia. Nothing can withstand her fire. But the following day, a new Federal ironclad, called the Monitor, suddenly appears to challenge her. It's a draw, as neither can disable the other, but the Virginia is destroyed two months later, to avoid capture.