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A card index to pre-1906 naturalizations for all the counties in Nebraska, western Iowa, and some counties in eastern Iowa in the 1930s and 1940s was compiled as a Works Progress Administration (WPA) project. This index has been microfilmed and can be searched at the Nebraska State Historical Society. Each card contains the name, country of origin, date of naturalization, and the court, county, and state of naturalization. The name of the state does not appear on cards for many Nebraska counties. The reverse side contains the type of naturalization and the volume and page number where the record is located. This index includes only those who received their final papers in Nebraska. It does not report those who only declared their intention in Nebraska. The Nebraska State Historical Society has over eighty percent of the naturalization records for the counties in the state from the district courts. The FHL and the society have large collections of U.S. District Court records (National Archives) on microfilm.