USS Constellation (1854), the last all-sail warship built by the United States Navy and current museum ship in Baltimore Harbor, is commissioned.

USS Constellation is a sloop-of-war, the last sail-only warship designed and built by the United States Navy. She was built at the Gosport Shipyard between 1853 and 1855. She was named for the earlier frigate of the same name that had been broken up in 1853. The sloop's primary armament was sixteen 8-inch (203 mm) shell-firing guns and four 32-pounder long guns, though she carried other guns as well, including two Parrott rifle chase guns. Constellation's career as a front-line unit was relatively short; after entering service in 1855, she served with the Mediterranean Squadron until 1858, and in 1859, she was assigned as the flagship of the Africa Squadron, where she served with the African Slave Trade Patrol. During the American Civil War (1861–1865), the ship returned to the Mediterranean to patrol for Confederate vessels. In late 1864, she returned to the United States to be decommissioned, as most of her crews' enlistments had expired. She spent the rest of the war out of service.