Researching Topics and Events

Note: The USCIS History Offices updates the guide with information on additional records and more detailed discussions of the records already included. Please subscribe to our GovDelivery update if you would like to receive notification of updates.

U.S. Citizenship and Immigration Services (USCIS) began operations on March 1, 2003. During the preceding century, the Immigration and Naturalization Service (INS) oversaw federal immigration and naturalization policy. Thus, students and scholars interested in the origins of USCIS and the policies it administers, as well as those studying the immigration policies now carried out by Customs and Border Patrol (CBP) and Immigration and Customs Enforcement (ICE), often begin their historical research in the records of INS. This guide will equip you with the knowledge necessary to identify and request historical INS files from both the National Archives and, for more recent files, USCIS.

For more than a century, the INS and its predecessor agencies generated numerous types of records and organized and indexed these records in a multitude of ways. Generally, INS records can be divided into two categories:

  • Records relating to individual immigrants, such as Naturalization Certificate files, and
  • Records that relate to subject, policy, administrative and correspondences files that document how INS administered immigration and nationality policies. This set of records provides information about how INS carried out its functions on a day-to-day basis.

If you are interested in researching a specific immigrant’s experiences, see our Guide to the Records of Individual Immigrants. If you are interested in researching the history of federal immigration agencies such as INS and the Border Patrol, or any aspect of twentieth century immigration and nationality policy, you should begin with the subject research guide.

Name Index to Bureau of Naturalization Correspondence

Research with INS’ historical files requires time, patience, and sometimes familiarity with unclear archival language. Students, and even experienced scholars who approach the records without proper preparation can quickly become frustrated. For example, archivists can seldom retrieve records on a given topic. Instead they need a specific Record Group (RG), entry, and file numbers.

The subject research guide will equip you with the knowledge necessary to identify and request historical INS files from both the National Archives and USCIS.

Today, most INS subject, policy, administrative, and correspondence files dated before 1956 are part of RG 85, Records of the Immigration and Naturalization Service (INS), at the National Archives in Washington, D.C. Within RG 85 the files are divided into separate entries depending on the date and to some extent the topic of the file.

Our INS Case, Correspondence, Policy and Administrative Records Overview research guide currently includes information about INS’s four main records series:

Updates to the research guide will cover additional records including records related to Chinese Exclusion Act enforcement. Please send us a message if you would like to receive notices about updates to the guide.



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