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In the United States, Flag Day (more formally, National Flag Day), is celebrated on June 14. It commemorates the adoption of the flag of the United States, which happened that day by resolution of the Second Continental Congress in 1777.National Flag Day | United States Flag | Stars and Stripes | Old Glory | Star Spangled Banner | BurningTaper.com
In 1916, Woodrow Wilson issued a proclamation that officially established June 14 as Flag Day; in August 1949, National Flag Day was established by an Act of Congress.
Flag Day is not an official federal holiday, though on June 14, 1937, Pennsylvania became the first (and only) U.S. state to celebrate Flag Day as a state holiday.
Title 36 of the US Code is the official statute on Flag Day; however, it is at the President's discretion to officially proclaim the observance.
The largest Flag Day parade is held annually in Troy, NY.