African American slavery arrived in California with the rush for gold in 1849, and continued for years after.
Slavery was outlawed in California in 1850, but laws required enforcement, and Southerners in California often found the law on their side, due to Southerners holding positions in the State’s courts. Often, the courts ruled in favor of the slaveholders rather than the freedom of slaves. However, the majority of whites in California did not approve of slavery. They looked down on those whites who enslaved blacks, and frequently turned a blind eye whenever a slave escaped from his master. It is worthy of note that at one time, the miners in Nevada City pooled their money together to buy the freedom of one black woman from her white master. I would also like to mention that many “free” blacks came to California and worked in the gold fields nearby and sometimes alongside white miners.
Grass Valley - Nevada City: The Morning Union October 19, 1917