Matsie For the Win!

Shiro Iishi performing a vivisection.

Unit 731 was a covert biological and chemical warfare research and development unit of the Imperial Japanese Army that undertook lethal human experimentation during the Second Sino-Japanese War (1937–1945) and World War II. It was responsible for some of the most notorious war crimes carried out by Japanese personnel.

Unit 731 was the code name of an Imperial Japanese Army unit officially known as the Kempeitai Political Department and Epidemic Prevention Research Laboratory. It was initially set up under the Kempeitai military police of the Empire of Japan to develop weapons of mass destruction for potential use against Chinese, and possibly Soviet forces.

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According to the 2002 International Symposium on the Crimes of Bacteriological Warfare, the number of people killed by the Imperial Japanese Army germ warfare and human experiments is around 580,000. According to other sources, the use of biological weapons researched in Unit 731’s bioweapons and chemical weapons programs resulted in possibly as many as 200,000 deaths of military personnel and civilians in China.

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On 6 May 1947, Douglas MacArthur, as Supreme Commander of the Allied Forces, wrote to Washington that “additional data, possibly some statements from Ishii probably can be obtained by informing Japanese involved that information will be retained in intelligence channels and will not be employed as ‘War Crimes’ evidence.” The deal was concluded in 1948.

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