The U.S. flag described by the Flag Act of 1777 had 13 stars.
The Second Continental Congress passed the Flag Resolution on June 14, 1777. It specified 13 alternating red and white stripes and 13 white stars on a blue field, representing the 13 states then forming the Union. The resolution did not prescribe a particular arrangement for the stars.
Later artists and flag makers used several arrangements, including circles, rows, and other patterns. The circular arrangement is strongly associated with the Betsy Ross flag, but historians do not have conclusive evidence that Ross designed the national flag. The famous story became widely popular decades after the Revolution.
The number of stars eventually increased as new states joined the Union. In 1960, Hawaii’s admission produced the current 50-star flag. The stripes, however, returned to 13 to represent the original states rather than continuing to grow.