The original United States flag had 13 stripes under the 1777 flag resolution.
On June 14, 1777, the Second Continental Congress adopted a resolution creating a national flag with thirteen alternating red and white stripes and thirteen white stars on a blue field. The thirteen elements represented the original Thirteen Colonies.
The resolution did not specify the exact arrangement of the stars. It stated that the stars should form a new constellation, leaving the design open to interpretation. The familiar circular arrangement is associated with later flag-making traditions, including the Betsy Ross legend, which is not established by the resolution itself.
As new states entered the Union, Congress increased the number of stars. In 1818, it set a lasting rule: the flag would return to thirteen stripes while adding one star for each new state. Thus the modern flag retains thirteen stripes but has fifty stars.