The battle is best remembered for inspiring Francis Scott Key to write The Star-Spangled Banner. Detained aboard the ship Minden, Key had gone to meet with the British to secure the release of Dr. William Beanes who had been arrested during the attack on Washington. Having overhead the British attack plans, Key was forced to remain with the fleet for the duration of the battle. Moved to write during the fort’s heroic defense, he composed the words to an old drinking song entitled To Anacreon in Heaven. Initially published after the battle as the Defense of Fort McHenry, it eventually became known as the Star-Spangled Banner and was made the National Anthem of the United States.

http://militaryhistory.about.com/od/warof1812/p/ftmchenry.htm