The first California flag flew for less than a month. The United States had declared war against Mexico on May 11, 1846, but information traveled slowly back then and it took until July 9 for the that news to reach the instigators of what came to be known as the Bear Flag Revolt.
In 1911, the state of California adopted the Bear Flag as the official California flag.
Symbolism on the California Flag
Grizzly bear: Strength
Lone star: Imitates the Texas Lone Star