INS Case, Correspondence, Policy and Administrative Records Overview

Early Immigration Correspondence files (1882-1912)

The Immigration Service’s first central filing system. Contains policy documents and correspondence covering issues important to the new agency, including administrative, legal, and fiscal matters.

Immigration Policy and Correspondence files (1906-1956), aka the “56,000 series”

The Immigration Service's second central filing system. A massive collection of policy and correspondence files covering all aspects of immigration policy, 1906-1956 and nationality policy from the mid-1930s to 1956.

Bureau of Naturalization Correspondence files (1906-1944)

The Bureau of Naturalization Service’s correspondence files, which includes detailed files on policy, program and administrative topics related to nationality.

Central Office (CO) subject files (1957-1995)

The INS’s third central filing system, including policy files from the second half of the twentieth century.

Early Immigration Correspondence files (1882-1912)

NARA Record Group 85, Entries 1-8

Location: National Archives (NARA), Washington, DC

Finding Aids: Reserve Index and various others (see below)

Upon its establishment in 1891 the Immigration Service inherited the files, and filing system of the Assistant Treasury Secretary who had previously overseen federal immigration policy. The new Immigration Service maintained the system and began incorporating its own correspondence into it. These early files, which were chronologically numbered, contain correspondence between field and headquarters officials, public correspondence, and policy documents.  The records cover all of the issues important to the new Immigration Service including administrative, legal, and fiscal matters, as well as individual immigrant cases.

Today the early correspondence records and associated indices make up entries 1-8 of RG 85.  The majority of the correspondence files themselves are found in entry 7, letters received 1882-1906, and entry 8, letters sent 1882-1912.  Entry 7 consists of letters received by the Secretary of the Treasury and then Commissioner of immigration arranged by letter number, 1 to 51609, with some files missing due to transfer to the “56,000 series” (see below).  Entry 8, letters received, is divided into three parts: The “E” series (2 vol.), which covers 1882-1887, is arranged chronologically, and contains an alphabetical index; the “T” series (14 vol.), which covers 1892-1903 and is also arranged chronologically; and the general letters sent series (342 vol.), which covers July, 1891 to March, 1912 and is arranged chronologically with most early volumes containing a full or partial alphabetical index. The general letters sent series duplicates much of the material in the “T” series, though at times it provides more complete coverage of administrative affairs.

Unfortunately, researchers seldom use these early records, largely because no single, easy to navigate index exists. The records are, however, partially indexed by the registry volumes that make up Entry 1, Register of Letter Received, 1882-1887 and Entry 3, Record of Correspondence/Registry of Letters Received, 1891-1903.  Together, these registers index large portions of Entry 7. Entry 1 registers are arranged chronologically and list the date, number, sender’s name and address, and subject for each letter. Entry 3 registers are arranged by date and letter number and list for each letter the subject, sender’s name and address, and, when appropriate, the volume and page number for the corresponding letter sent in Entry 8. Volumes 1-9 and 13-25 of Entry 3 contain alphabetical listings of subjects and correspondents. The indices for volumes 10-12 of Entry 3 make up Entry 2. In addition to the registers, there is the Entry 5 subject index, which covers correspondence from roughly 1900-1910. The 11 box index consists of 3x5 cards arranged by subject and within subjects by city (for example “Automobiles, Boston” to “Automobiles, Spokane”). The index, sometimes referred as the “Reserve Index,” references letters in Entry 7 and early “56,000 files” in Entry 9 described below.

Immigration Policy and Correspondence files (1906-1956), aka the “56,000 series”

NARA Record Group 85, Entry 9

(NARA ARC Identifier 559947 / MLR Number A1, 323, A1, 9-A )

Location: National Archives (NARA), Washington, DC

Finding Aid: Subject Index to Correspondence and Case Files of the Immigration and Naturalization Service (NARA microfilm publication T-458)

In 1906, after it had accumulated over 50,000 files, the Immigration Service adapted its numerical file system by subdividing file numbers with a “ / ” and suffix number. Thus, the file numbers could be expanded into nearly a thousand separate files (e.g. 53500/01, 53500/02, etc.). The file numbers were still generated in approximate chronological sequence and the numbers had no correlation to any particular subject – a fact that often vexes researchers today. The 56,000 series closed in March of 1957 with the last file numbers issued being 56000/01 and above, hence the “56,000 series” name. 

For over half a century the 56,000 series served as the major repository for Immigration Service records and it contains an overwhelming amount of material documenting nearly every aspect of American immigration history. Much of the series consists of policy and correspondence files covering the interpretation and enforcement of immigration policies.  The files generally contain correspondence between Immigration Service field and headquarters offices, correspondence between the Service and the public, official policy statements (including drafts and revisions of those statements), memoranda, and various related documents.  Among these documents are files on individual immigrants whose cases raised questions about the enforcement, application, or interpretation of immigration law. Additionally, administrative files cover every facet of the Immigration service’s operations, including personnel and financial issues. Naturalization program administrative files began to be filed in the 56,000 series after 1933 when the Naturalization and Immigration Services merged into a single agency. By 1944, the separate naturalization subject and correspondence file series (discussed below) closed and all INS subject and correspondence files were placed in the 56,000 series.

Beginning in the 1940s, the Immigration Service began incrementally transferring the 56,000 series to NARA, Washington, DC and the final set of 8000 boxes of files was arrived there in 1996. In addition to including the last of the files yet to be transferred to NARA, this final group of records contained over a thousand files previously believed to have been recalled from the Archives and destroyed. All 56,000 series files are now accessible to researchers and reside in Entry 9 of RG 85.

The 56,000 File series is indexed by the Subject Index to Correspondence and Case Files of the Immigration and Naturalization Service (NARA microfilm # T-458) an alphabetical subject index referencing file numbers. Consulting the T-458 index is an essential first step for any researcher planning to conduct topical research within INS’s policy and correspondence records.  When using the index, researchers should consider that it was created by Immigration Service bureaucrats during the first half of the 20th century and adjust their search terms appropriately. Researchers should also know that the T-458 indexes both the 56,000 series and the naturalization correspondence series. The INS interfiled cards from both indices and microfilmed them together. Thus, for example, cards from both series will appear next to each other under the entry for “Anarchists.”  Familiarity with each file structure will generally prevent confusion between the two series. Unfortunately, there is no name index to the 56,000 file series. So, while as many as half of the files in the series relate to specific individuals, it often nearly impossible to locate an individual’s file by his or her name.  Researchers who believe that an immigrant may have a 56,000 file (such as immigrants removed from the US or involved in a lengthy appeal case) may contact the USCIS History Office for guidance on determining if a file exists.

Bureau of Naturalization Correspondence files (1906-1944)

NARA Record Group 85, Entry 26

(ARC Identifier 563066 / MLR Number A1 26, A1 26-A )

Location: National Archives (NARA), Washington, DC

Finding Aids: Subject Index to Correspondence and Case Files of the Immigration and Naturalization Service (NARA microfilm publication T-458), Name Index to Bureau of Naturalization Correspondence Files, 1906-1946 (NARA microfilm publication A3388)               

With the creation of the Naturalization Service in 1906, a parallel series of subject correspondence files was created specifically for nationality matters. The naturalization series contains detailed files on policy, program, and administrative topics and provides the type of rich documentation for nationality matters that the 56,000 series does for immigration matters. The naturalization series also includes a vast number of files containing correspondence from immigrants and citizens who had questions about their nationality status or nationality policy in general. The naturalization correspondence series closed in 1944. After that date, INS filed program, policy, and administrative files in the 56,000 series and documents related to the cases of individual immigrants in the immigrants’ A-Files. 

Today all of the surviving Bureau of Naturalization Correspondence files are part of RG 85. The majority of the files fall into Entry 26 but several smaller entries include additional material, most notably Entries 30-34 which contain correspondence and program material related to the service’s Citizenship Education Programs.

Though the file numbers for the naturalization series appear similar to that of the 56,000 series, the naturalization series system differs significantly in that the initial file number corresponds to a particular topic. For example, all the files in 35/ series relate to the general topic of “soldiers and sailors.” To locate all files on a subject created 1906 to 1944, researchers should identify to the appropriate subject code.  A list of known subject codes is available from the USCIS History Office. Like the 56,000 series, the naturalization series are indexed by the T-458 (see above).  The index points to specific file numbers, allowing for targeted research within subject headings.  The series is also referenced by a name index which includes headings for all individuals with whom the Naturalization Service had correspondence during the years 1906-1944. NARA has assigned the index microfilm publication number A3388 (Bureau of Naturalization Correspondence Index). A copy of the A3388 name index is also available for use in the USCIS History Office.

Central Office (CO) subject files (1957-1995)

NARA Record Group 85, Entry P-4A

(NARA ARC Identifier 1273013 / Local Identifier / MLR Number P 4A, P 4B )

Location: National Archives (NARA) Washington, DC [select records dating prior to 1975]; USCIS [records 1975-1995, requires FOIA request]

Finding Aid: Central Office Subject File Catalog (USCIS History Library)

In 1956 the INS implemented a new filing system designed to remedy many of the problems associated with 56,000 series. The new system, known as the Central Office or “CO” File System, gave all files the CO prefix and keyed the first 599 index numbers to related sections of Title 8 of the Code of Federal Regulations, Aliens and Nationality. For example, the files under CO 212.3 contain policy and correspondence concerning aliens excludable on medical grounds.  Files above 599 were given subject headings and cover all other aspects of INS’s administrative and operational functions. The CO File System houses only subject-related documents, as distinguished from individual case files, which were thereafter filed in each individual’s A-File. The CO File System also mandated that correspondence and policy documents be filed separately. 

Today, surviving CO files will be found in either RG 85, entry P-4A or still with USCIS.  Files in RG 85 generally date from 1957 to 1974. Unclassified files at NARA, processed and made available to researchers within the past two years, are stored in Washington, DC. Classified files with NARA are stored in the College Park facility and viewing them requires a request to the NARA FOIA office. Files still with USCIS date from 1957-1995, though coverage is better for years prior to the 1980s. Viewing CO files still with USCIS requires a request to the USCIS FOIA Program.

CO files are indexed by the Central Office Subject File Catalog, which lists the files numerically and alphabetically by subject.  The Catalog also references the corresponding 56,000 series file for subjects active prior to 1957. A copy of the Central Office Subject File Catalog is available to researchers in the USCIS History Office.  Researchers who need assistance determining the location of a particular file should contact the History Office for assistance.



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