How to Find Cook County Naturalization Records

Please note: I am new to naturalization searching and the information given below is a first draft. I'd welcome comments and suggestions on how to improve this help page.

The Circuit Court information sheet titled Cook County Naturalization Records provides an excellent summary of how to search for naturalization records in Cook County. Also see the Circuit Court Archives' Important Information about Naturalization Records to learn what information you'd expect to find on documents from various years.

Up through 1929, Cook County naturalization could take place in one of five courts: Circuit Court, Superior Court, County Court, Criminal Court or the United States District Court. After 1929, all naturalization was done through the District Court. If you are researching an individual who naturalized before the 1890s, the Chicago Voter Registration Lists for 1888, 1890, and/or 1892 (available on Ancestry.com) may list the court.

In you have an Ancestry.com subscription, try searching the Soundex index found under Selected U.S. Naturalization Record Indexes, 1791-1992. Select "Illinois, Indiana, Wisconsin, Iowa" from the States menu and choose "Soundex Index to Naturalizations ... " You will need to obtain the soundex code for the surname you're searching. Try the Rootsweb Soundex Converter. Once you've selected the correct group of records, play the high-low number game to focus in on the given name you're looking for. (The cards are alphabetical by given name within each Soundex code.)

If you live in the Chicago area, you can use the Soundex index at the Circuit Court Archives and at IRAD at NEIU. It can also be accessed on Family History Library microfilm. Indexes specific to the four county courts are also available on microfilm and those indexes (not the Soundex) are available at the Wilmette Family History Center.

Here are some example links to Family History Library Catalog entries:

Criminal, County, Circuit and Superior Court Naturalization Records
(this link is to a page with many different catalog entries)

Indexes to Superior Court Naturalization Records

Criminal Court Minors and Old Soldiers Naturalization Index and Final Naturalization Index, 1871-1903

County Clerk's Index of record of naturalization papers of which no record can be found, ca. 1918-1923

Locating the Actual Records

Naturalization records can be found at the Circuit Court Archives (Circuit, Criminal, County, and Superior Courts, 1871-1929), at NARA Great Lakes (District Court), and on Family History Library Film (all courts).

For curent fees and information on how to request records, please see the websites linked above. I can occasionally retrieve single records from the Circuit Court Archives if I am making the trip for other reasons. Email me for details.