California Naturalization Records Online at Ancestry|
(these require an Ancestry subscription)
California Naturalization Records and Indexes Online at FamilySearch (free)
- California Federal Naturalization Records, 1887-1991 (requires payment) for naturalizations done in federal courts; includes digitized images of the naturalization records from the Riverside (Southern California), Los Angeles (Central California), and San Bruno (Northern California) branches of the National Archives; coverage varies by court; most records are Petitions for Naturalization or Declarations of Intention.
- California, State Court Naturalization Records, 1850-1986 (most are before 1930) (requires payment) includes index and images of naturalization records from California courts in Amador, Butte, Colusa, El Dorado, Fresno, Napa, Orange, Placer, Santa Barbara, Santa Clara, Sonoma, Stanislaus, Sutter, Yolo, and Yuba counties; coverage varies by county.
- California Naturalization Records (requires payment) includes Petitions for Naturalization, 1918-1991, and Declarations of Intention, 1940-1991 for Los Angeles; and Naturalization Petitions, 1955-1991 for San Diego
California Naturalization Records Online at Fold3
- California: County Naturalizations, 1849-1985 from FamilySearch; for Alameda, Amador, Alpine, Butte, Calaveras, Clousa, El Dorado, Fresno, Glenn, Lake, Lassen, Los Angeles, Mendocino, Napa, Nevada, Orange, Placer, Sacramento, San Francisco, Sonoma, Santa Clara, Stanislaus, Santa Barbara, San Benito, San Diego, Solano, Sutter, Yolo, and Yuba counties. Coverage varies by county.
- California, Northern U.S. District Court Naturalization Index, 1852-1989 from National Archives microfilm publication M1744
- California, Southern District Court (Central) Naturalization Index, 1915-1976 from National Archives microfilm publication M1525
(searches are free - downloading the images requires payment)