Uploaded August 2026 | Updated September 2026, 2 weeks ago
Before Japan surrendered, American intelligence had already identified Ishii Shiro, biological warfare research in Harbin, experimental germ bombs, and reports of plague attacks against Chinese communities.
The evidence appears in a secret U.S. War Department report dated July 26, 1945.
In this episode of Pacific Front Untold, Jenny Chan and Didi Hotane examine what the United States knew about Japan’s biological warfare program before the war ended. The report describes weapons involving plague, cholera, anthrax, typhoid, infected fleas, contaminated grain, and attacks on water supplies.
It also examines reported biological attacks in Ningbo, Changde, Jinhua, and other parts of China. Although American investigators remained cautious about some Chinese reports, they concluded that Japan had probably used biological warfare experimentally in at least one case.
The report raises a disturbing question: If American authorities already knew about Ishii and Japan’s biological weapons program, why did the truth remain hidden after the war?
After Japan’s surrender, U.S. authorities pursued information from Ishii and his associates. Key members of the Unit 731 network escaped war crimes prosecution in exchange for their research.
Source featured in this episode:
U.S. War Department, Military Intelligence Division, “Japanese Biological Warfare,” Intelligence Research Project No. 2263, July 26, 1945.
This document can be found in Sheldon Harris papers, Box 1, Folder 5, at the Hoover Institute or at the National Archives, Entry 146, Box 253, Folder 3502.
Pacific Atrocities Education preserves overlooked histories of the Asia-Pacific War through archival research, educational publishing, and public programs.
Please subscribe, share this episode, and support our work preserving these records before they disappear.
Support the Hidden Pacific Archives series:
$5 — buys a coffee to keep us going during long archive days
$15 — covers lunch at Coupa Cafe while researching at Hoover Institution
$25 — covers one day of parking at Hoover
$50 — supports translation of 2 pages of archival material
$100 — supports half a day of scanning
$200 — supports a full day of scanning
$500 — helps sponsor one archive-based episode, including research, scanning, translation prep, visuals, and production
Every contribution helps us scan, translate, and bring rarely seen archival materials from WWII Asia into public view.
Donate here: pacificatrocities.org/support-us
#Unit731 #BiologicalWarfare #PacificWar #WWIIHistory #JapaneseWarCrimes #PacificFrontUntold
Before Japan surrendered, American intelligence had already identified Ishii Shiro, biological warfare research in Harbin, experimental germ bombs, and reports of plague attacks against Chinese communities.
The evidence appears in a secret U.S. War Department report dated July 26, 1945.
In this episode of Pacific Front Untold, Jenny Chan and Didi Hotane examine what the United States knew about Japan’s biological warfare program before the war ended. The report describes weapons involving plague, cholera, anthrax, typhoid, infected fleas, contaminated grain, and attacks on water supplies.
It also examines reported biological attacks in Ningbo, Changde, Jinhua, and other parts of China. Although American investigators remained cautious about some Chinese reports, they concluded that Japan had probably used biological warfare experimentally in at least one case.
The report raises a disturbing question: If American authorities already knew about Ishii and Japan’s biological weapons program, why did the truth remain hidden after the war?
After Japan’s surrender, U.S. authorities pursued information from Ishii and his associates. Key members of the Unit 731 network escaped war crimes prosecution in exchange for their research.
Source featured in this episode:
U.S. War Department, Military Intelligence Division, “Japanese Biological Warfare,” Intelligence Research Project No. 2263, July 26, 1945.
This document can be found in Sheldon Harris papers, Box 1, Folder 5, at the Hoover Institute or at the National Archives, Entry 146, Box 253, Folder 3502.
Pacific Atrocities Education preserves overlooked histories of the Asia-Pacific War through archival research, educational publishing, and public programs.
Please subscribe, share this episode, and support our work preserving these records before they disappear.
Support the Hidden Pacific Archives series:
$5 — buys a coffee to keep us going during long archive days
$15 — covers lunch at Coupa Cafe while researching at Hoover Institution
$25 — covers one day of parking at Hoover
$50 — supports translation of 2 pages of archival material
$100 — supports half a day of scanning
$200 — supports a full day of scanning
$500 — helps sponsor one archive-based episode, including research, scanning, translation prep, visuals, and production
Every contribution helps us scan, translate, and bring rarely seen archival materials from WWII Asia into public view.
Donate here: pacificatrocities.org/support-us
#Unit731 #BiologicalWarfare #PacificWar #WWIIHistory #JapaneseWarCrimes #PacificFrontUntold
