Happy 235 birthday to the American Flag and happy 237 birthday to the U.S. Army. Flag Day is celebrated on June 14 of each year. It commemorates the adoption of the flag of the United States, in 1777. The United States Army also celebrates the Army Birthday on this date; Congress formally created the “American continental army” on June 14, 1775. The photos below featuring Old Glory and the US Army are from the DDN Collection.