Flag of California (public domain image on Wikipedia).
Official State Flag of California
Designed by William Todd (nephew of Mary Todd Lincoln, wife of Abraham Lincoln), the historic bear flag was raised at Sonoma, California in 1846 by American settlers in revolt against Mexican rule (officially adopted as the state flag of California in 1911). All State Flags
Symbols on California's Flag
The once common California grizzly bear (also the official state animal) portrays strength; the star represents sovereignty; the red color signifies courage; and the white background stands for purity.
The Bear Flag Revolt
On June 14, 1846, a small band of settlers marched on the Mexican garrison at Sonoma and took the commandant prisoner. They issued a proclamation which declared California to be a Republic independent of Mexico. This uprising became known as the Bear Flag Revolt (after the hastily-designed flag depicting a grizzly bear and a five pointed star over a red bar and the words "California Republic."
The grizzly bear was a symbol of great strength while the star made reference to the Lone Star of Texas. The flag only flew until July 9, 1846 when it was learned that Mexico and the United States were already at war. Soon after, the Bear Flag was replaced with the American flag. It was adopted as the State Flag by the State Legislature in 1911.