Naturalization is the process by which an alien becomes an American citizen. It is a voluntary act; naturalization is not required.

Prior to September 27, 1906, any "court of record" (municipal, county, state, or Federal) could grant United States citizenship. Often petitioners went to the court most geographically convenient for them. As a general rule, the National Archives does not have naturalization records created in state or local courts. However, a few indexes and records have been donated to the National Archives from counties, states, and local courts. Researchers should contact the National Archives facility serving the state in which the petitioner resided to determine if records from lower courts are available. In certain cases county court naturalization records maintained by the National Archives are available as microfilm publications.  Records from state and local courts are often at state archives or county historical societies.

Beginning September 27, 1906, United States naturalization law imposed a fee structure that encouraged the transfer of naturalization to Federal courts. Some lower courts continued  the practice for a while. Therefore, researchers may need to look at lower courts records if the National Archives does not maintain a record of naturalization from the early to middle 20th century.

In general, naturalization was a two-step process* that took a minimum of five years. After residing in the United States for two years, an alien could file a "declaration of intention" ("first papers") to become a citizen. After three additional years, the alien could "petition for naturalization" (”second papers”). After the petition was granted, a certificate of citizenship was issued to the new citizen. These two steps did not have to take place in the same court.  [*Exceptions can include cases of derivative citizenship, processes for minor aliens 1824-1906, and special consideration for veterans.]

If a naturalization took place in a Federal court, naturalization indexes, declarations of intention (with any accompanying certificates of arrival), and petitions for naturalization usually will be in the National Archives facility serving the state in which the Federal court is located. No central index exists.

To ensure a successful request with the National Archives, researchers should include:

  • name of petitioner (including known variants);
  • date of birth;
  • approximate date of entry to the US;
  • approximate date of naturalization;
  • where the individual was residing at the time of naturalization (city/county/state);
  • and country of origin

In most cases, the National Archives will not have a copy of the certificate of citizenship. Two copies of the certificate were created – one given to the petitioner as proof of citizenship, and, after September 26, 1906, one forwarded to the Immigration and Naturalization Service (INS). Certificates of citizenship were issued by the Federal courts until October 1991 when naturalization became an administrative function under the INS.

All INS records are now overseen by the US Citizenship and Immigration Services (USCIS). USCIS maintains duplicate copies of court records (including the certificate of citizenship) created September 27, 1906-March 31, 1956 within Certificate Files (C-Files). Beginning on April 1, 1956, INS began filing all naturalization records in a subject’s Alien File (A-File). C-Files and certain A-Files can be requested through the USCIS Genealogy Program. If you are a naturalized citizen seeking your own documentation, you may submit a Freedom of Information Act (FOIA) request to USCIS to obtain a copy of your A-File and/or request a replacement certificate of citizenship from USCIS.

Please Note:

  • National Archives staff can only issue a certified copy of a document in our custody (see 44 USC 2116 and 44 USC 3112).
  • The National Archives does not have authority to issue an apostille. The US Department of State has the authorization to issue an apostille of a copy of a document certified by the National Archives.
  • The National Archives does not have the authority to issue a certification of non-existence of a record, and can only issue a negative search letter. Negative results for a search of National Archives holdings only indicates that a naturalization record is not in the possession of the National Archives. It does not verify that a file does not exist elsewhere.
  • USCIS has exclusive authority over matters concerning citizenship records after 1906 and can provide a Certification of Non-Existence of a Record of Naturalization (see “About Further Research”).