Dear Ms. Stanfield,
Thank you for posting your request on History Hub!
We searched the National Archives Catalog and located the series Select Documents Released Under the Nazi War Crimes and Japanese Imperial Government Disclosure Acts Relating to Japanese War Crimes in the General Records of the Department of State (Record Group 59) that includes some records related to Japanese Army Unit 731. These records have been digitized and may be viewed online via the Catalog. You may contact the National Archives at College Park - Textual Reference (RDT2) at firstname.lastname@example.org with questions about these records.
Next, we located the series Second Release of Name Files Under the Nazi War Crimes and Japanese Imperial Government Disclosure Acts in the Records of the Central Intelligence Agency (Record Group 263) that contains numerous records related to Japanese doctors and scientists, including Ishii, Shiro who was a lieutenant general of Unit 731. These records have been digitized and may be viewed online in the Catalog. Please contact RDT2 for assistance with these records.
We also located the series First Release of Name Files Under the Nazi War Crimes and Japanese Imperial Government Disclosure Acts in Record Group 263 that consists of name files of Axis personnel accused of committing war crimes, or of belonging to criminal organizations, during World War II. The series Intelligence and Investigative Dossiers Personal Files in the Records of the Army Staff (Record Group 319) also contains information about Japanese war criminals. Because these series are arranged by name of individual, a specific name is required before a search of the records can be conducted. These records have not been digitized. For access to and information about them, please contact RDT2.
In addition, we located the series Card Files Relating to Japanese War Criminals, 1945? - 1949?, the series Records of Trials of Accused Japanese War Criminals Tried at Manila, Philippines, 1945-1947, and the series Records of Trials and Clemency Petitions for Accused War Criminals Tried at Yokohama, Japan, 1947--1948 in the Records of Allied Operational and Occupation Headquarters, World War II (Record Group 331) that might be of interest to you. These records have not been digitized. For assistance with these and similar records, please contact RDT2.
Further, we located the series Far East Name Index to the Series "Case Files, 1944-1949" in the Records of the Office of the Judge Advocate General (Army) (Record Group 153) that may include records related to Japanese doctors and scientists. The index has been digitized and may be viewed online via the Catalog. It relates to the series Case Files, 1944-1949, which has not been digitized. Please contact RDT2 with questions about these records.
Plus, we located the series Records of Japanese Atrocities Against Prisoners of War (POWs), 1942-1948 in the Records of the Adjutant General’s Office, 1917 - 1985 (Record Group 407) that may contain some relevant information. These records have not been digitized. You may contact RDT2 with any questions you might have about them.
And we suggest that you review some helpful information on NARA’s website in this Japanese Interim Report and in the press release 100,000 Pages Declassified in Search for Japanese War Crimes Records.
Due to the COVID-19 pandemic and pursuant to guidance received from the Office of Management and Budget (OMB), NARA has adjusted its normal operations to balance the need of completing its mission-critical work while also adhering to the recommended social distancing for the safety of NARA staff. As a result of this re-prioritization of activities, you may experience a delay in receiving an initial acknowledgement as well as a substantive response to your reference request from RDT2. We apologize for this inconvenience and appreciate your understanding and patience.
Finally, more information about UNIT 731 – Japan's Biological Warfare Project may be located online. You may wish to contact the NATIONAL ARCHIVES OF JAPAN to see if they can offer any additional assistance.
We hope this information is helpful. Best of luck with your research!