Flag Day commemorates the adoption of the  U.S. Flag by the Second Continental Congress on June 14, 1777. In 1916, President Woodrow Wilson issued a proclamation that officially established June 14 as Flag Day. It is not an official federal holiday, though on June 14, 1937, Pennsylvania became the first and only state to celebrate Flag Day
as a state holiday, beginning in the town of Rennerdale. In August 1949, National Flag Day was established by an Act of Congress.