George M. Cohan composed this spirited march in 1906, as part of the musical, George Washington, Jr. The song became wildly popular and reportedly sold over 1 million copies of sheet music. According to the Library of Congress, Cohan took his inspiration for the song from a chance meeting he had with a veteran of the Civil War who carried in his hands a torn and tattered American flag.

You're a grand old flag,
You're a high flying flag
And forever in peace may you wave.
You're the emblem of
The land I love,
The home of the free and the brave.
Ev'ry heart beats true
Under Red, White and Blue,
Where there's never a boast or brag.
Should auld acquaintance be forgot,
Keep your eye on the grand old flag!

                    — George M. Cohan