Californians had a couple of complaints that might have led to secession if the federal government had failed to appease them. Washington recognized a potential for Pacific Coast secession no later than the early 1860s as evidenced by the motivations for the Pacific Railroad Acts.*
The state's chief complaint stemmed from racism against Chinese residents by white Californians. That's why California opposed legislation providing racial equality and voting rights for both whites and minorities. For example, California did not ratify the 14th and 15th Amendments until
1959 and
1962 respectively.
Even though Asian residents never totaled more than 10% of the state's population, two-thirds of her lynch victims between 1849 - 1902 were Chinese.** America's biggest lynching happened in Los Angeles in 1873 while Grant was President and nineteen Chinese were victims. One can only shudder to imagine the anti-Chinese terrorism that might have swept the state were Asians abruptly given voting rights, while representing over half the voters as did blacks in the former Confederate states in 1868.***
The federal government appeased California's racism by adopting Acts that led to a decline in the number of Chinese residents, which dropped from 9% of California's population in 1870 to 4% in 1900. First, unlike black immigrants, Chinese were denied citizenship via the 1870 Naturalization Act. Second, the 1875 Page Act sharply restricted the number of Chinese women permitted to enter the country. This prevented Chinese men from having children who would get citizenship and voting as a birthright via the 14th Amendment. At the time 95% of America's Chinese were male, and interracial marriage was rare.
Next came a series of federal
Chinese Exclusion Acts designed to reduce the number of Asian residents. The first, in 1882, stopped Chinese immigration for a decade. The 1892
Geary Act extended the exclusion for another decade. In 1904 the exclusion acts were made permanent.
A second motivation for California secession was the federal adoption of Greenback fiat currency in 1862. During the Civil War California merchants refused to accept Greenbacks at face value. Only specie (gold or silver coins) would be taken at face value. Similarly, California would only accept specie as payment for taxes. The federal government appeased California on this issue as well. Even though California (and Oregon) defied the Legal Tender Act the federal government took no action against their rebellion. After the War the federal government agreed to payoff all war bonds in specie and make all Greenbacks redeemable in specie at face value.
Without federal appeasement, California secession might've been as likely as Southern secession in 1850 absent the Clay compromise of that year.
* William Borneman,
Rival Rails, Kindle Loc. 883
** Jean Pfaelzer,
Driven Out, 52
*** Merton Coulter,
The South During Reconstruction, 133