Under the Flag Resolution of 1777, 13 stars represented the United States’ original states.
The Second Continental Congress passed the resolution on June 14, 1777. It specified thirteen alternating red and white stripes and a union of thirteen white stars on a blue field. The stars represented the “new constellation” formed by the independent states.
The original design reflected the thirteen colonies that declared independence from Great Britain. As new states joined the Union, the flag’s number of stars changed. Congress temporarily increased both stars and stripes to fifteen in 1794 after Vermont and Kentucky joined.
The Flag Act of 1818 established the lasting arrangement: the flag would retain thirteen stripes for the original colonies, while the number of stars would match the number of states. Later stars were added on Independence Day after new states entered the Union. The familiar fifty-star flag dates from 1960.