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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.

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