The national anthem of the United States of America is called "The Star-Spangled Banner". It was written in 1814 by Francis Scott Key, a 35-year-old lawyer and amateur poet, after witnessing the bombardment of Fort McHenry by British ships of the Royal Navy in Chesapeake Bay during the Battle of Baltimore in the War of 1812. Key was inspired by the large U.S. flag, known as the Star-Spangled Banner, flying triumphantly above the fort during the U.S. victory. He wrote a poem titled "Defence of Fort M'Henry", which was later set to music and became the national anthem of the United States in 1931.