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This entry was originally written by Dwight A. Radford, Thelma Berkey Walsmith, and Nell Sachse Woodard in Red Book: American State, County, and Town Sources.
As with other states, prior to 1906 a person might have filed for naturalization in any court in the state; for this time period, there are no guides for locating a naturalization in the state other than for those records that were entered at federal district court. Many of those naturalization records have been gathered and are located at either of the National Archives regional branches: Pacific (San Bruno) or Pacific (Laguna Niguel) (see page 12). These collections include the Northern U.S. Circuit Court (1855–1905) in San Francisco; U.S. District—Northern District (1846–1989) at San Francisco and San Jose; and the U.S. District Eastern Court (1917–58). The FHL also has a large microfilm collection of the NARA microfilm as well as a large collection of citizenship records filed in California counties.