"The Star-Spangled Banner," written in Baltimore, turns 209 years old

BALTIMORE -- It has been 209 years to the day since Francis Scott Key wrote the "The Star-Spangled Banner" in Baltimore. 

It was originally penned as a poem by Francis Scott Key the morning after a 25-hour bombardment on Fort McHenry, known as The Battle of Baltimore During The War of 1812.

The British had already marched on Washington and set fire to the White House when they set their sights — and ammunition — on the last defense of the United States' industrial port.

Key was aboard a ship in the harbor and squinted through smoke to see who had won, as the sun began to break. A large American flag was raised. Key saw it and wrote a poem that became the national anthem.

The actual flag Key saw — the Star-Spangled Banner — is now housed in a climate-controlled, light-protected chamber at the Smithsonian's National Museum of American History in Washington, D.C.

After the War of 1812, the flag and the words it inspired became a sensation. Key's poem was quickly set to a popular — and ironically British — tune and was soon rebranded as "The Star-Spangled Banner."

In 1931, it finally became America's official national anthem.