Unit 731

Disease Prevention and Water Supply Unit 731 was a very large Japanese biological warfare team, that primarily experimented on civilians of various ethnicities, mainly Russian and Chinese, but also Manchus, Mongolians, and others. It was part of the Kwantung Army (關東軍), which was the most prestigious of Japan's armies. It was located in Pingfang (平房区 or 平房區), in what was then Japanese Manchukuo (Manchuria) and is now part of China. It started operations in 1932 and continued through World War II. Victims at Pingfang included hapless civilians, common criminals, and alleged spies.Unit 731: Japan's Secret Biological Warfare in World War II by Peter Williams & David Wallace (1989). Free Press. ISBN 0029353017. From 1942-1945, more than 1000 Allied soldiers were also experimented upon by Unit 731 at a prisoner of war camp located in Mukden (now known as Shenyang, 沈阳). General (石井 四郎) was the mastermind, creator and leader of the unit.
The Unit 731 annual budget was larger than that of any Japanese university, and was reportedly as large as the total tax revenue of Manchoukuo.Gold, Hal. Unit 731 Testimony, Charles E Tuttle Co., 1996. ISBN 4-900737-39-9.
The unit performed vivisections without anesthetic and conducted experiments in the field of biological warfare on their unfortunate victims. Other experiments on victims included frostbite treatment, syphilis experimentation (including rape and forced pregnancy), grenade testing, centrifuge testing, testing of flamethrowers, and other gruesome experiments. After the war ended the entirety of Unit 731 was given immunity by the United States in return for the unit's data. An estimated 3,000 prisoners were killed at Pingfang during the experiments, which left no prisoner alive.http://www.unit731.org/Experiments.html Unit 731: Japan's Biological Warfare Project] Unit731.org. There were survivors at the Mukden camp, but attrition was very high.
Unit 731 also spread biological weapons over Chinese cities and against Chinese troops. These usually resulted in minor epidemics, but in the case of the 1942 , "germs of cholera, dysentery, typhoid, plague, anthrax and paratyphoid were all used", and Chinese losses from disease were very high but "inestimable". Disease spread back to the Japanese army with casualties of more than 10,000.China Handbook 1937-1938: A Comprehensive Survey of Major Developments in China in Six Years of War, edited by Hollington K. Tong (July 1943) Chungking, China: The Chinese Ministry of Information.In addition to the 1942 use of biological weapons in Chekiang, Dr. P. Z. King documented the following uses of biological weapons in China by the Japanese Army. In all cases, a Japanese airplane(s) dropped suspicious material (grain, fleas, granules, cloth) into areas where plague was not endemic; the material was clinically identified to contain Yersinia pestis, the plague bacteria.
*Chuhsien, Chekiang Province, October 4, 1940: bubonic plague, 21 deaths
*Ningpo (宁波市), Chekiang Province, October 29, 1940: bubonic plague, 99 victims
*Kinhwa (金东区), November 28, 1940: Japanese planes dropped granules containing Y. pestis, but no plague infections reported
*Changteh (常德会战), Hunan Province, November 4, 1941: plague, 6 cases of plague
A smaller Japanese army unit, also located in Manchuria, known as Unit 100 was also conducting germ warfare testing on prisoners. Unit 100 was operated under the Kempeitai, the Japanese military police. Two other units were involved in biological warfare research: Detachment Nami 8604 (or Unit 8604) and Detachment Ei 1644 (or Unit 1644). Unit 8604 was under the command of the Japanese Southern China Area Army, located in Canton (Guangzhou), China. Unit 1644 was located in Nanking, China and conducted human vivisections.Materials on the Trial of Former Servicemen of the Japanese Army Charged with Manufacturing and Employing Bacteriological Weapons. Foreign Languages Publishing House, 1950, 535 pp.
==Post-war==
Japanese activity in the area of biological warfare was strongly suspected by the US as early as 1939, and the first public documentation of Japanese biological weapons was on April 9, 1942 with a thorough report by Dr. P. Z. King that was published in July 1943 in The China Handbook (pp. 679-682).
Towards the end of the war, the Soviet Union invaded Manchuria (under the terms of the Yalta Conference between the Allied Powers) and captured a few key personnel from Unit 731. Other members of the unit eventually managed to return to Japan, often secretly. The Pingfang site was found in near total destruction, having been destroyed by Unit 731 before the advance of Soviet troops. Almost all of the documents were destroyed by the unit.
The Tokyo War Crimes Trials took place during 1946 to 1948. They were not the only war crime trials of the Japanese, but they were the primary trials. Despite having copious evidence of biological warfare having been conducted by the Japanese, no charges were filed against members of Unit 731. The United States government had contact with Unit 731 members in Japan and interviewed them extensively, including Ishii. General Douglas MacArthur (who was then the Supreme Commander for the Allied Powers in Japan) gave immunity to Ishii and all other members of the unit. The Soviet Union had repeatedly asked that Ishii and the other members of Unit 731 located in Japan be tried as war criminals, but they had little influence within Japan. Among the enormous amounts of documents presented at the Tokyo War Crimes Trials, only brief — and perhaps accidental — mention was given to biological weapons.
In December 1949 in the border city of Khabarovsk, the Soviet Union tried and convicted 11 members of Unit 731 and one member of Unit 100. The trial was based on evidence from a few key documents and the confessions of those on trial. The trial was closed to Western observers. The prison sentences ranged from 2 to 25 years in a labor prison camp.
The convicted members of Unit 731 were (years of prison sentence in parentheses):
# General (a.k.a., Otozoo Yamada) (山田 乙三), commander-in-chief of the Kwantung Army (25)
# Lieutenant General Ryuiji Kajitsuka, chief of Medical Administration in the Kwantung Army (25)
# Major General Kiyoshi Kawashima who was in charge of the experimental division (25)
# Lieutenant General Takaatsu Takahashi, who was head of the Veterinary Division (25)
# Major Tomio Karasawa who was in charge of a section that produced germs on large scale (25)
# Lieutenant Colonel Toshihide Nishi, who was responsible for breeding fleas, rats, mice, and guinea pigs (20)
# Major Masao Onoue bred laboratory animals and trained laboratory assistants (12)
# Major General was chief of Unit 8604 and Unit 1644 (20)
# Lieutenant Zensaku Hirazakura produced bacteria and poisons while in Unit 100 (10)
# Senior Sergeant Kazuo Mitomo manufactured anthrax, glanders cattle plague and sheep plague (15)
# Corporal Norimtsu Kikuchi attempted to produce a medium for growing typhoid and other bacteria (2)
# Private Yuji Kurushima was a laboratory orderly who dissected fleas, caught rats and put bacteria in test tubes, and was involved in biological warfare against China (3)
According to Kojima Takeo, a captain in the Shantung Army who spent time at Unit 731, he was among the 1050 prisoners who were considered war criminals and were sent to China from Russia in 1949 for further imprisonment. Not all of the prisoners were necessarily affiliated with Unit 731, but they all would have been captured in northern China. 
===The unpunished===
Why were the Unit 731 members, other than those captured by the Soviets, never tried? Both the Soviet Union and the US were keen to get as much information as possible on biological weapons. This was shown by the extensive interviews by US officials of Unit 731 members, the closed Khabarovsk trial, and the one-time joint interrogation of Ishii by the Soviets and the US (later denied by the Soviets). The United States wanted to obtain Japanese information about biological weapons and the only way to gain detailed information seemed to be to offer immunity. The Soviet trial at Khabarovsk showed that this was not necessarily the case, but a closed trial in Japan was probably not feasible. MacArthur's offer of complete and total immunity may have been excessively broad. The immunity, however, was a betrayal by MacArthur of his own troops, a few of whom were abandoned by MacArthur in the Philippines, and later transported to Mukden by the Japanese, winding up as guinea pigs for infection experiments. The Khabarovsk trial had been essentially dismissed by the US as a show trial by the Soviets, though it has now been established that the confessions and evidence reported from the trial were essentially completely accurate.
Many of the scientists and medical doctors of Unit 731 went on to have scientific careers after the war at universities, research institutes and pharmaceutical companies. Two important figures at Unit 731, Lieutenant-Colonel Ryoichi Naitō and Lieutenant-General founded a multinational company, the , which would later be embroiled in a scandal for knowingly importing HIV-tainted blood into Japanese blood banks. Naitō even became a member of the New York Academy of Sciences. Japan's sins of the past: The memories of Japanese biological attacks on China in the 1940s are still fresh. Many Chinese want an apology by Justin McCurry (Thursday 28 October 2004 11.21 EDT) The Guardian.
The nearly-complete list of members of Unit 731 was finally revealed by the National Archives of Japan in 2018 after being petitioned by a group led by Katsuo Nishiyama, professor emeritus of Shiga University of Medical Science.Names of 3,607 members of Imperial Japanese Army’s notorious Unit 731 released by national archives (Apr 16, 2018) The Japan Times. The list of 3,607 members includes "52 surgeons, 49 engineers, 38 nurses and 1,117 combat medics".
The table below shows the activities before and after the war of unpunished members of Units 731, 100 and 1644, and of people who held academic positions that facilitated the units' activities. All information is based on Williams & Wallace and Gold. All positions during the war are at Unit 731 unless otherwise noted.
Name 	Activity during the war 	Position after the war
Shiro Ishii 	Chief of Unit 731 	Cambridge University lecturer Richard Drayton has claimed that Ishii served as a bioweapons consultant to the US military at Fort Detrick, Maryland.An ethical blank cheque: British and US mythology about the second world war ignores our own crimes and legitimises Anglo-American warmaking by Richard Drayton (Monday 9 May 2005 19.37 EDT) The Guardian. It was also alleged that he converted to Christianity and opened a free clinic for children in Japan. He died in 1959 from throat cancer.
(lieutenant colonel) 	chief financial officer of the Kwantung Army (and therefore in charge of Unit 731 finances), observed poison gas experimentation on humans at Pingfan 	Raised horses, started a failed business, was active in several International Olympics committees
Dr. Kiyoshi Asanuma 	Identified the tick insect vector of epidemic hemorrhagic fever 	Worked at the Research Institute for Natural Resources
Dr. Asahina 	Assisted Dr. Asanuma 	Chief of the Entomology Section of the Health and Welfare Ministry's Preventive Health Research laboratories
Dr. Ken'ichi Kanazawa 	Performed tests on ticks 	Chief of the research section of the Takeda Pharmaceutical Company
Dr. Kōji Andō 	Headed the vaccine-producing laboratory at Dairen 	Professor of Tokyo University's Infectious Diseases Research Institute
Dr. Tachiomaru Ishikawa 	Pathologist 	President at Kanazawa University's medical school
Professor Ren Kimura 	Bacteriologist under whom Ishii studied, sent young medical graduates to Unit 731 	Dean of Nagoya Municipal Medical School, won the Japan Academic Institute Prize, was a member of the New York Academy of Sciences (NYAS)
Dr. Masao Kusami 	Leader of the pathology squad 	Professor at the Showa University of Pharmacology
Dr. Tōru Ogawa 	Researcher on typhoid and paratyphoid, Unit 1644 	Professor, Faculty of Medicine, Nagoya City University
Kōzō Okamoto 	Pathology squad leader at Pingfang, carried out human vivisection 	Director of both the Kyoto University and Kinki University medical departments
Dr. Kazu Tabei 	Researched dysentery, typhoid, and paratyphoid at Pingfang, fed typhoid to human experimentees 	Professor of bacteriology at Kyoto University
Dr. Takeo Tamiya 	"Talent scout" at Tokyo Imperial University 	Dean of Tokyo Imperial University's Medical School, director of the Japanese National Cancer Centre, president of the Japan Medical Association
Dr. Yoshi Tsuchiya 	Leader of diagnostic division in Nanking 	Honorary professor at Juntendo University
Dr. Toshikazu Yamada 	Director of a bacteriological unit 	Professor of Kumamoto University, temporary director of Hygiene for the City of Yokohama
Dr. Taboku Yamanaka 	Civilian technician at Nanking 	Dean of Osaka Medical School
Dr. Hisato Yoshimura 	Directed frostbite experiments on humans 	President of Kyoto Prefectural Medical College, adviser to the Japanese Antarctic Expedition, President of the Japanese Meteorological Society, received the Order of the Rising Sun, Third Class, President of Kobe Women's University
Dr. Shinpei Ejima 	Dysentery research 	Joined the Japanese National Institute of Health (JNIH)
Major Dr. Jun'ichi Kaneko 	Bomb expert 	Joined the JNIH
Professor Saburō Kojima 	Tokyo University Laboratory for Communicable Diseases, Director of the Den Ken research department, visited the Nanking human experimentation unit 	Director of Second Division, National Institute of Health; worked in the Health and Welfare Ministry's National Preventive Health Research Centre
Lieutenant-General Yujirō Wakamatsu 	Commander of Unit 100 	Studied streptococcal infections in children at the JNIH
Dr. Yukimasa Yagisawa 	Plant disease expert 	Secretary of the Japanese Penicillin Association who worked at JNIH
Dr. Kiyoshi Hayakawa 	Attempted to obtain yellow fever virus samples from the US before the war, member of the Singapore Detachment 	Manager of the Hayakawa Medical Company
Colonel Tomosada Masuda 	Ishi's deputy 	General medical practice in Chiba Prefecture
Dr. Hideo Futaki 	Headed the tuberculosis research squad, vivisection team leader 	Co-founded Green Cross with Naitō & Kitano, President of S. J. Company
Colonel Dr. Kiyoshi Ōta 	Military surgeon, led the raid on Changteh 	General medical practice in Yamaguchi Prefecture
Dr. Masahiko Takahashi 	Pingfang's leading plague researcher 	General medical practice in Chiba Prefecture
 	Accounting department in the Shansi detachment, later acknowledged that he knew of the unit's activities 	Governor of Tokyo
Lieutenant-Colonel Seiichi Niizuma 	Actively prevented information from becoming available to pre-war crime trial investigators 	Worked at the Tokyo Research Institute of the Japan Self-Defense Force
Lieutenant-Colonel Dr. Ryōichi Naitō	Attempted to obtain yellow fever virus samples from the US before the war, duplicitously worked as an interpreter for a US war-crimes investigator immediately after the war	Worked as a private surgeon, founded the Japan Blood Bank, co-founded the Green Cross Corporation with Masaji Kitano & Hideo Futaki, member of the NYAS, Japanese Science Society award, Order of the Rising Sun
Lieutenant-General Masaji Kitano 	Second in command 	Co-founded Green Cross with Naitō & Futaki, formed a vaccine-producing company with Tamiya which went bankrupt, chief of the Tokyo branch of the Japan Blood Bank under Naitō
Lieutenant-Colonel Dr. Naitō Ikeda 	Experiments on humans with hemorrhagic fever and tetanus 	Ran a blood disease clinic in Osaka, published some of the details of his Unit 731 work in a scientific journalInfection experiments with the flea and lice of epidemic hemorrhagic fever, Japan Infectious Diseases Society Journal, August 20, 1968, vol. 42, no. 5.
Dr. Shirō Kasahara 	Conducted experiments on humans of Songo (hemorrhagic) fever 	Emeritus vice-president of the Kitasato hospital and Research Unit
Tadashi Yamashita 	Photographer 	Radiographer
Masakuni Kurumizawa 	Assistant technician at vivisections 	Farmer
Amitani Shogo 	Tokyo University Laboratory for Communicable Diseases 	Remained at this lab after the war, received the Asahi Prize for outstanding scientific performance
Ando Koji 	Head of Dalian Laboratory 	Professor of the Tokyo University Laboratory for Communicable Diseases, Head of the Central Laboratory for Experimental Animals
Kasuga Tadayoshi 	Dalian Laboratory 	Kitasato Research Laboratory, Ministry of Education Pertussis Research Team
Kimura Yasushi 	Professor at Kyoto University 	Assistant head of the Japan Medical Association, President of the Nagoya City University of Medicine
Kobayashi Rokuzo 	Professor at Keio University 	Director, First Division, National Institute of Health
Miyagawa Yoneji 	Head of the Tokyo University Laboratory for Communicable Diseases 	Toshiba Biophysics and Biochemistry Research Laboratory
Murata Yoshisuke 	Unit 1644 	JNIH
Ogata Tomio 	Assistant professor at Tokyo University Laboratory for Communicable Diseases 	Professor, Faculty of Medicine, Tokyo University
Okamoto Kozo 	Pathology research team 	Dean of the Faculty of Medicine at Kyoto University and Kinki University
Sonoguchi Tadao 	Biological warfare development 	Vice Principal, School of Hygiene at Japan Self-Defense Forces
Tanaka Hideo 	Plague-carrying fleas team 	Dean, Faculty of Medicine, Osaka City University
Toda Shozo 	Professor, Kyoto University 	Member of the Special Committee for Antarctic Research, President of Kanazawa University
Yanagizawa Ken 	Tuberculosis research team 	Head of the JNIH
===Japanese exhibition===
During 1993-1994, an exhibition concerning the activities of Unit 731 toured 61 locations in Japan. It included both written and in-person testimony from surviving Unit 731 members. A large part of the testimony was translated and published by Gold. The testimony largely corroborated previously published evidence.
==Lessons unlearned==
In 1969 US President Richard Nixon unilaterally terminated US biological weapons research, which led to the 1972 The many signatories include the US, Russia (as the legal heir to the Soviet Union's treaty obligations) and Japan, but not China. China, as of 2024 is believed to have abided by the treaty even though it is not a signatory. Colonel Guo Ji-wei of the Chinese People’s Liberation Army (PLA) and past or former members of the PLA have discussed their use both in the context of supposed humaneness and the possibility of ethnic targeting.The U.S. could soon face a threat ‘more powerful’ than nuclear weapons: Researchers around the globe are tinkering with viruses far deadlier than covid-19 by Ashish K. Jha et al. (November 11, 2024 at 5:45 a.m. EST) The Washington Post.Ultramicro, Nonlethal, and Reversible: Looking Ahead to Military Biotechnology by Guo Ji-wei & Xue-sen Yang (July-August 2005) Military Review (Army University Press).Weaponizing Biotech: How China’s Military Is Preparing for a ‘New Domain of Warfare’ by Elsa B. Kania & Wilson VornDick (August 14, 2019) Center for a New American Security.Weaponizing Biotech: How China's Military Is Preparing for a 'New Domain of Warfare' by Elsa B. Kania & Wilson VornDick (August 14, 2019) Defense One.推进强军伟业的战略思考 [Strategic thinking on promoting the great cause of strengthening the military] by 张仕波著 (Zhang Shibo-zhu) & 张仕波 (Shibo Zhang) (2017) 人民出版社 [People's Publishing House]. . Russia meanwhile expanded its Cold War-era biological weapons research facility in 2024.Satellite images show major expansion at Russian site with secret bioweapons past by Joby Warrick & Jarrett Ley (October 25, 2024 at 5:00 a.m. EDT) The Washington Post.
==Gallery==
File:A sketch of the prison cells, done by a member of Unit 731. The octagonal sketch represents the pressure chamber.jpg|Sketch of prison cells with octagonal pressure chamber for carrying out human experiments
File:Unit 731 victim.jpg|Germ warfare experiment on a prisoner
==See also==
*Rape of Nanjing
*Comfort women
*Nazi human experimentation
*Weapons of mass destruction
==Notes==
==References==
Category:Crimes against humanity
Category:Misnomers
Category:War crimes
Category:Japan
Category:Japanese war crimes denial
Category:Shōwa Statism
Category:World War II