Francis Scott Key was inspired to compose the poem "Defence of Fort McHenry" after seeing the flag flying above Ft. McHenry on the morning of September 14, 1814, after the fight had concluded. These lyrics were written by Key and placed to the music of a famous song at the time, "To Anacreon in Heaven" by John Stafford Smith. On September 14, 1814, Francis Scott Key stood on the deck of an American truce ship and saw the flying of Fort McHenry's big garrison flag above the walls. He'd seen Britain's twenty-five-hour assault of the fort, and flying the American flag was a victorious sign of valor and persistence for Key.