The Bear Flag is the official flag of the U.S. state of California. The precursor of the flag was first flown during the 1846 Bear Flag Revolt and was also known as the Bear Flag. A predecessor, called the Lone Star Flag, was used in an 1836 independence movement; the red star element from that flag appears in the Bear Flag of today.

The flags of the U.S. states, territories, and the District of Columbia exhibit a variety of regional influences and local histories, as well as different styles and design principles. Modern U.S. state flags date from the turn of the 20th century, when states considered distinctive symbols for the 1893 World's Columbian Exposition in Chicago, Illinois. Most U.S. state flags were designed and adopted between 1893 and World War I.