When the American Revolution broke out in 1775, the colonists weren’t fighting united under a single flag. Instead, most regiments participating in the war for independence against the British fought under their own flags. In June of 1775, the Second Continental Congress met in Philadelphia to create the Continental Army—a unified colonial fighting force—with the hopes of more organized battle against its colonial oppressors. This led to the creation of what was, essentially, the first “American” flag, the Continental Colors.
In the United States, Flag Day is celebrated on June 14. It commemorates the adoption of the flag of the United States on June 14, 1777 by resolution of the Second Continental Congress.
The Flag Resolution, passed on June 14, 1777, stated: "Resolved, That the flag of the thirteen United States be thirteen stripes, alternate red and white; that the union be thirteen stars, white in a blue field, representing a new constellation." This design was created by Francis Hopkinson, a Continental Congressman from New Jersey and a consultant to the design of the Great Seal of the United States.
The United States Army also celebrates the U.S. Army birthday on this date; Congress adopted "the American continental army" after reaching a consensus position in the Committee of the Whole on June 14, 1775.
In 1916, President Woodrow Wilson issued a proclamation that officially established June 14 as Flag Day; on August 3, 1949, National Flag Day was established by an Act of Congress. Flag Day is not an official federal holiday. Title 36 of the United States Code, Subtitle I, Part A, CHAPTER 1, § 110, is the official statute on Flag Day; however, it is at the president's discretion to officially proclaim the observance. On June 14, 1937, Pennsylvania became the first U.S. state to celebrate Flag Day as a state holiday, beginning in the town of Rennerdale. New York Statutes designate the second Sunday in June as Flag Day, a state holiday.
Quincy, Massachusetts, has had an annual Flag Day parade since 1952 and claims it "is the longest-running parade of its kind" in the U.S. The largest Flag Day parade had been held annually in Troy, New York until 2017, which based its parade on the Quincy parade and typically draws 50,000 spectators. In addition, the Three Oaks, Michigan, Flag Day Parade is held annually on the weekend of Flag Day and is a three-day event and they claim to have the largest flag day parade in the nation as well as the oldest. In Washington, D.C., Flag Day is celebrated heavily through the 7th and 8th Wards of the city. It is said that Clyde Thompson is the "Godfather of Flag Day". It is tradition in these wards to slow smoke various meats and vegetables.