California abolished slavery even before it became a U.S. state:1849

Statehood: 1849–1850

In 1847–49, California was run by the U.S. military; local government continued to be run by alcaldes (mayors) in most places, but now some were Americans. Bennett C. Riley, the last military governor, called a constitutional convention to meet in Monterey in September 1849. Its 48 delegates were mostly pre-1846 American settlers; eight were Californios. They unanimously outlawed slavery and set up a state government that operated for 10 months before California was given official statehood by Congress on September 9, 1850, as part of the Compromise of 1850.^[32] After Monterey, the state capital was variously San Jose (1850–1851), Vallejo (1852–1853) and Benicia (1853–1854), until Sacramento was finally selected in 1854.
Californios (dissatisfied with inequitable taxes and land laws) and pro-slavery Southerners in lightly populated, rural Southern California attempted three times in the 1850s to achieve a separate statehood or territorial status separate from Northern California. The last attempt, the Pico Act of 1859, was passed by the California State Legislature, signed by the state governor, approved overwhelmingly by voters in the proposed "Territory of Colorado" and sent to Washington, D.C., with a strong advocate in Senator Milton Latham. However, the secession crisis in 1860 led to the proposal never coming to a vote.^[33][34]

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• 7.4 Statehood: 1849–1850