On June 14, 1777, Congress adopted a resolution, proposed by John Adams,
for a new flag.
The 13 stars, white on a blue field, represented a new constellation:
"We take," said George Washington, "the star from Heaven, the red from
our mother country [Britain], separating it by white stripes, thus
showing that we have separated from her, and the white stripes shall go
down to posterity representing liberty."
In 1818 Congress enacted a statute finally fixing the style and pattern
of the "Star-Spangled Banner" as we know it today.
The idea of an annual day specifically celebrating the Flag is believed
to have originated in 1885. Flag Day -- the anniversary of the Flag
Resolution of 1777 -- was officially established by the Proclamation of
President Woodrow Wilson on May 30th, 1916.