September 9, 1850: California Becomes the 31st State of the Union

California became the 31st state on September 9, 1850, admitted directly as a free state under the Compromise of 1850, without ever passing through territorial status — one of the few states in the country to skip that step entirely. The admission came just four years after the Bear Flag Revolt, the short-lived 1846 uprising in Sonoma that first raised the flag California still flies today.

From Bear Flag to Statehood

In June 1846, a group of American settlers in Mexican California, distrustful of rumors that Mexico intended to expel them, seized the town of Sonoma and declared an independent California Republic. They raised a hand-painted flag bearing a grizzly bear and a red star, designed by William Todd, a nephew of Mary Todd Lincoln. The republic lasted twenty five days. Word arrived that the United States and Mexico were already at war, and California passed to American control as part of that conflict.

The 1848 discovery of gold at Sutter's Mill changed everything that followed. Tens of thousands of people arrived within two years, and California's population grew fast enough that it applied for statehood without ever organizing as a territory first — an unusual path shared by only a handful of states. The admission was politically difficult: California's free-state constitution threatened the balance between free and slave states in Congress, and its statehood became one piece of the Compromise of 1850, a set of measures that held the Union together for another decade. President Millard Fillmore signed the admission act on September 9, 1850.

The Flag Itself

The Bear Flag became California's official state flag by legislative act in 1911, and its exact design was standardized in 1953 under California Government Code Section 420. The statute is precise: a red, five-pointed star in the upper left corner of a white field, a grizzly bear walking left on all four paws across a grass plot in the center, the words CALIFORNIA REPUBLIC between the grass plot and a red stripe running the length of the flag along the bottom. The original 1846 flag was destroyed in the fire that followed the 1906 San Francisco earthquake, so the flag flown today is a standardized reconstruction of that design, not the surviving original.

The grizzly bear on the flag is a subspecies now extinct everywhere. The bear used as the model for the 1953 standardization was Monarch, the last California grizzly held in captivity, who died in 1911 — the same year the flag itself was adopted. Read the full history and statute of the California flag on our category page.

Fly It on California's Birthday

Under the United States Flag Code as amended July 7, 1976, a state flag flown on the state's birthday takes its place beneath the United States flag, and September 9 is the one date every year the California flag has an official reason to go up. California also observes Admission Day as a legal observance, and some California cities and municipal offices mark it directly.

Have a California flag ready before September 9 and it is on the flagpole for the day. Shop California state flags in every outdoor size, nylon and two-ply polyester, made in the United States. The full list of every state's admission date is on our state birthdays page.