Arizona Naturalization and Citizenship
Persons living in the territory in 1848 and those residing in the area of the Gadsden Purchase were automatically granted U.S. citizenship. Naturalization records for later immigrants were filed in the district courts. They were recorded in the U.S. district court from September 1906 until 1912 when Arizona became a state. Since then, naturalization records have been filed in the superior courts, except for Maricopa County in which the U.S. district court has had jurisdiction since 1919.
Declarations, petitions, certificates, and other early records from about 1864 to 1912 are located at the National Archives—Pacific Region (Laguna Nuguel) and the Department of Libraries, Archives and Public Records. The Family History Library has copies of many of these Arizona naturalization records on microfilm for 1864-1955.
For records after September 1906, contact the National Archives—Pacific Region (Laguna Niguel), the local office of the Immigration and Naturalization Service, or the U.S. district court.