In what year was USS Constitution launched?

USS Constitution was launched in 1797.

The United States Navy's heavy frigate entered Boston Harbor on October 21, 1797. It was one of six original frigates authorized under the Naval Act of 1794, which established a stronger early national navy. The ship was built at Edmund Hartt's shipyard in Boston and designed by Joshua Humphreys.

The launch was not smooth. Constitution initially slid only about 27 feet before the ways settled under its weight. After the launching ways were rebuilt, the ship moved a further 31 feet during another attempt. It finally entered the harbor after a month of work, with Captain James Sever breaking a bottle of Madeira wine over the bowsprit.

Constitution became famous during the War of 1812, when victories over British warships helped earn it the nickname “Old Ironsides.” It remains the world's oldest commissioned warship still afloat. Its name refers to the Constitution of the United States, not to a Revolutionary War vessel.