National Flag Day and "The Star Spangled Banner"

In the United States, Flag Day is celebrated on June 14th to commemorate the adoption of the flag of the United States of America on June 14, 1777 by resolution of the Second Continental Congress. This is also the day the United States Army celebrates its birthday.

On September 14, 1814, Francis Scott Key penned a poem which was later set to music and in 1931 became America's national anthem, "The Star Spangled Banner." The poem originally titled, "The Defence of Fort M'Henry," was written after Key witnessed the Maryland fort being bombarded by the British during the war of 1812. The sight of those "broad stripes and bright stars" inspired thousands. If you've never heard the story before, try the video below. 

Have you ever heard this story before? Do you know the words to this poem/song? Can you think of any other piece of writing that has influenced thousands?