Although the United States mobilized a few ships during the American Revolution, it did not officially establish the U.S. Navy until 1797. Relatively small, the Navy served in America's wars between its establishment and the Civil War and patrolled the coastline during peacetime. Following the secession crisis, the Navy was dramatically expanded to better enforce the Union blockade of the Confederacy and became the subject of several substantial technological innovations, most notably the development of the ironclad. During this time, the Navy was managed by the Navy Department.
Nathan Miller, The U.S. Navy: A History 3rd ed., (Annapolis, MD: Naval Institute Press, 1997), 11-142; Stephen Howarth, To Shining Sea: A History of the United States Navy, 1775-1998 (Norman: University of Oklahoma Press, 1999), 3-212.