The U.S. Bureau of Investigation Case File Archives covers important investigations by an agency of the U.S. government later known as the FBI. The archives contain over 2.2 million pages of original historical documents. It includes tales of espionage during World War I, case files for German aliens who were politically suspect, records pertaining to Mexican neutrality, and reports dealing with alleged violations of Federal laws providing a fresh insider's perspective to the history of this time period.

The U.S. Bureau of Investigation Case File Archives presents case files from the Federal Bureau of Investigation which until 1935 was called the Bureau of Investigation (BOI). The Investigative Reports contained in this collection (1908-1922) number hundreds of thousands of cases, each a few pages to a few dozen pages long. Cases cover interstate commerce and foreign affairs during the Progressive Era, espionage and sabotage during World War I, prohibition, gangsters, and more. General Investigative Records (1908-1922) contain reports, correspondence, and memorandums regarding alleged violations of Federal law. Investigative Records Relating to German Aliens (1915-1920) pertain to German aliens, considered politically suspect at the time. Investigative Records Relating to Mexican Neutrality Violations (1909-1921) include the first investigations of conditions on the Mexican border when in 1916 General John J. Pershing first led the U.S. Army into Mexico.

The archival collection includes reports and other documents relating to persons being investigated for working against the country's interests during Mexican civil wars and contains much about political, social, and economic conditions at the U.S.-Mexico border at the time.

Investigative Records Transferred from the Department of Justice ( Bureau Section Files)(1920-21) consist of investigative reports from other Department of Justice areas whose investigative functions were absorbed by the BOI.

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Other related services include:

• eBooks
• EBSCO Discovery Service

• Over 2.2 million pages of original historical documents
• Investigative Reports (1908-1922)
• General Investigative Records (1908-1922)
• Investigative Records Relating to German Aliens (1915-1920)
• Investigative Records Relating to Mexican Neutrality Violations (1909-1921)
• Investigative Records Transferred from the Department of Justice (Bureau Section Files)(1920-21)