|
|
|
|
|
|
| Alameda | 1853 | Contra Costa, Santa Clara | Oakland | |
| Alpine | 1864 | El Dorado, Amador, Calaveras | Markleeville | |
| Amador | 1854 | Calaveras | Jackson | |
| Butte | 1850 | Original County | Oroville | |
| Calaveras | 1850 | Original County | San Andreas | |
| Colusa | 1850 | Original County | Colusa | |
| Contra Costa | 1850 | Original County | Martinez | |
| Del Norte | 1857 | Klamath | Crescent City | |
| El Dorado | 1850 | Original County | Placerville | |
| Fresno | 1856 | Merced, Mariposa | Fresno | |
| Glenn | 1891 | Colusa | Willows | |
| Humboldt | 1853 | Trinity | Eureka | |
| Imperial | 1907 | San Diego | El Centro | |
| Inyo | 1866 | Tulare | Independence | |
| Kern | 1866 | Tulare, Los Angeles | Bakersfield | |
| Kings | 1893 | Tulare, Fresno | Hanford | |
| Lake | 1861 | Napa | Lakeport | |
| Lassen | 1864 | Plumas, Shasta | Susanville | |
| Los Angeles | 1850 | Original County | Los Angeles | |
| Madera | 1893 | Mariposa, Fresno | Madera | |
| Marin | 1850 | Original County | San Rafael | |
| Mariposa | 1850 | Original County | Mariposa | |
| Mendocino | 1850 | Original County | Ukiah | |
| Merced | 1855 | Mariposa | Merced | |
| Modoc | 1874 | Siskiyou | Alturas | |
| Mono | 1861 | Calaveras, Fresno | Bridgeport | |
| Monterey | 1850 | Original County | Salinas | |
| Napa | 1850 | Original County | Napa | |
| Nevada | 1851 | Yuba | Nevada City | |
| Orange | 1889 | Orange | Santa Ana | |
| Placer | 1851 | Placer | Auburn | |
| Plumas | 1854 | Plumas | Quincy | |
| Riverside | 1893 | San Diego, San Bernardino | Riverside | |
| Sacramento | 1850 | Original County | Sacramento | |
| San Benito | 1874 | Monterey | Hollister | |
| San Bernardino | 1853 | Los Angeles | San Bernardino | |
| San Diego | 1850 | Original County | San Diego | |
| San Francisco | 1850 | Original County | San Francisco | |
| San Joaquin | 1850 | Original County | Stockton | |
| San Luis Obispo | 1850 | Original County | San Luis Obispo | |
| San Mateo | 1856 | San Francisco | Redwood City | |
| Santa Barbara | 1850 | Original County | Santa Barbara | |
| Santa Clara | 1850 | Original County | SSan Jose | |
| Santa Cruz | 1850 | Original County | Santa Cruz | |
| Shasta | 1850 | Original County | Redding | |
| Sierra | 1852 | Yuba | Downieville | |
| Siskiyou | 1852 | Shasta, Klamath, Oregon | Yreka | |
| Solano | 1850 | Original County | Fairfield | |
| Sonoma | 1850 | Original County | Santa Rosa | |
| Stanislaus | 1854 | Tuolumne | Modesto | |
| Sutter | 1850 | Original County | Yuba City | |
| Tehama | 1856 | Colusa, Butte, Shasta | Red Bluff | |
| Trinity | 1850 | Original County | Weaverville | |
| Tulare | 1852 | Mariposa | Visalia | |
| Tuolumne | 1850 | Original County | Sonora | |
| Ventura | 1872 | Santa Barbara | Ventura | |
| Yolo | 1850 | Original County | Woodland | |
| Yuba | 1850 | Original County | Marysville |
Linda Simpson |