On Sept. 14, 1814, Francis Scott Key peered through clearing smoke to see an enormous flag flying proudly after a 25-hour British bombardment of Baltimore's Fort McHenry. Key was inspired to write a poem, which was later set to music. Even before "The Star-Spangled Banner" became our national anthem, it helped transform the garrison flag with the same name into a major national symbol of patriotism and identity. The flag has had a colorful history, from its origins in a government contract through its sojourn with several generations of a Baltimore family to its eventual donation to the Smithsonian Institution.