Congress adopts the standardized US flag of 1818

Background. Prior to 1818, the United States lacked a consistent flag design for newly admitted states. The Flag Act of 1795 had increased stars and stripes to fifteen, but subsequent state admissions did not result in official flag updates. Between 1794 and 1818, there were no official U.S. flags with sixteen, seventeen, eighteen, or nineteen stars, creating a gap in the visual representation of the Union.

Legislative Action. On April 4, 1818, Congress enacted the Flag Act (3 Stat. 415). This legislation established the permanent number of stripes at thirteen, representing the original colonies, while stipulating that the number of stars would correspond to the number of states in the Union. The act provided a mechanism for updating the flag design as new states were admitted.

Design Standardization. The 1818 Act resolved the ambiguity of previous years by fixing the stripe count and linking the star count directly to statehood. This standardized the flag's appearance, ensuring that the number of stars accurately reflected the political composition of the United States at any given time, unlike the earlier period where official flags for intermediate state counts did not exist.