At its core, the American Civil War was a land conflict. More than three million men(and a handful of women) fought for four years along a thousand-mile front, and more than seven hundred thousand of them died either of battlefield wounds or(more often) of disease. The national government won the war and preserved the union because the northern public proved willing to sustain the Lincoln administration through four long years of bloodshed and sacrifice, and the South lost it because it could not match northern superiority in either manpower or industrial production. Nevertheless, sea forces played an important role in the conflict, and helped to determine both the trajectory and, very likely, the length of the war. Moreover, the two sides embraced dramatically different conceptions of the role that sea forces could or should play in the war, conceptions that were the product of divergent cultures and economies.

From the beginning, a significant part of the economy of the British colonies in New England and New York had derived from maritime activities – fishing, whaling, and of course trade – and this sea-based economy continued after independence was secured in 1783. For a time, the southern states, too, maintained a symbiotic relationship with the sea. From the Potomac River in Virginia to the Rio Grande in Texas, the southern coastline was more than 3,500 miles long, and included both the commodious sounds of the Carolinas as well as scores of natural harbors. Along the Atlantic seaboard, the rivers that flowed across the Piedmont and Tidewater from the Appalachian Mountains to the Atlantic, combined with the natural waterway along the coast created by the offshore islands, meant that most of the commerce in the southern states moved by water.