On June 14, 1777, during the Revolutionary War the United States Continental Congress declared the "Stars and Stripes" to be the national flag which later came to be known as Flag Day.
The original intent of Flag Day made clear the importance of the thirteen stripes of alternating red and white. It also reinforces the thirteen white stars in blue background as a declaration of a new beginning for the American colonies.
June 14 also became known as the birth date of the U.S. Army when Congress adopted "the American continental army" on June 14, 1775.
A century later, in 1916, President Woodrow Wilson proclaimed June 14 as Flag Day. Although, it wasn't until 1949 when the U.S. Congress passed a statute for establishing June 14 as Flag Day. Since its passage, Flag Day has been celebrated in places like Fairfield, Washington and Appleton, Wisconsin.