California Admission Day

Next Saturday, 9 September 2023

California Admission Day on September 9 commemorates the day when California was admitted into the Union as the 31st state in 1850, after being ceded to the United States by Mexico in 1848.

California Admission Day is not a public holiday in California, which means that businesses, schools, and government offices remain open.


In 1846 the United States declared war on Mexico. At the time, the territory of California in Mexico had a lot of American settlers as inhabitants, who staged a revolution against the Mexican government and captured Sonoma, declaring the area as the California Republic. On July 9 of the same year, Lieutenant Revere of the Navy arrived in Sonoma and placed a United States flag in the territory, officially declaring California as a possession of the United States. 

The Treaty of Guadalupe Hidalgo was signed in 1848 effectively ending the war between the United States and Mexico. Having been defeated, Mexico had to cede some territory to the United States. The population in this territory wasn't very big, so Congress took its time to organize the territory. Eventually, gold was discovered at Sutter's Mill in California, starting what became known as the Gold Rush. A huge influx of immigrants and American settlers, seeking to find work and some gold. Due to the increase in population and wealth, it became imperative for Congress to organize the territory, and establish local governments and law services. 

At the time, a territory needed to have 60,000 inhabitants in order to achieve statehood, which usually took a long time to happen. Before the Gold Rush, emigration to California was so low that it would have possibly taken decades for it to become a state. However, tens of thousands of people around America and the world moved to California just in 1849 trying to get a slice of the gold wealth, and the population quickly grew over 60,000. Due to this, California achieved straight statehood in just around 2 years of incorporating the territory of the United States and was officially admitted into the Union on September 9, 1850, as a free-labor state. 

California Admission Day Celebrations

On this day, some organizations and businesses in California may have special events happening to commemorate the holiday.

Schools will often dedicate the day to educating the students about the admission of California into the United States, and organize activities and events about it. 

If you're a history buff, today is the perfect day to visit some museums in California and learn more about the origins of the state.

California Admission Day
California Admission Day

California Admission Day - Next years

Monday, 09 September 2024

Tuesday, 09 September 2025

Wednesday, 09 September 2026

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