Unit 731

Historical use of Biological Warfare

According to the book A Plague Upon Humanity: The Secret Genocide of Axis Japan's Germ Warfare Operation, 2004:

"The first recorded instance of a planned effort to wipe out enemy forces in warfare with infectious disease occurred in colonial American during the French and Indian Wars, the plan included as its goal the extermination of entire civilian populations of Indians. The instigator was Sir Jeffrey Amherts, governor general of the North American colonies and general and commander-in-chief of the North American British Forces. In June 1763 Amherst ordered Colonel Henry Bouquet to disseminate smallpox to Naive American tribes in the Ohio-Pennsylvania region whom Bouquet's troops were fighting."

This practice continued in the U.S. for the next century or more, resulting in massive devastation of Native American tribes and greatly easing the way for the white men to take over the Indian territories.

Unit 731

"Unit 731" was a medical research team of the Japanese Imperial Army. They conducted biological experiments on prisoners of war, resulting in the death of more than 3,000 Chinese and Russian prisoners. The Japanese were working on developing bacteriological weapons, testing them on the prisoners. (Chinese estimates of the number of prisoners killed run as high as 20,000)

The germ warfare program resulted in deaths beyond those of the prisoners, however. According to the book A Plague Upon Humanity: The Secret Genocide of Axis Japan's Germ Warfare Operation, 2004:

"As of 2002, historical researches in China had estimated the number of people killed by Japanese germ warfare and human experiments to be approximately 580,000. This is the figure that was presented and mutually agreed upon at the International Symposium on the Crimes of Bacteriological Warfare, a conference on the subject of Japanese bio-war attended by scholars and investigative journalists held in December 2002 in the city of Changde, Hunan Province".

(I will note, though, that this is the highest figure I've seen in any book I've looked at, and that the figures cited by other sources are considerably smaller.)

There were other similar units, a few of which included Branch 673 (for plague carrying), Unit 543 near the Soviet Border, and the South Manchurian Railway Sanitary Institute and Unit 100 where research on use of biological weapons against animals and plants was conducted. Unit 1644 was the group established in Nanking after the Nanking Massacre/Rape of Nanking had taken place

The main individual behind the project was Shiro Ishii who was born on June 25th, 1892.

History behind Unit 731

The stage was set when the Japanese took over Manchuria on March 1, 1932 declared the state of Manchukuo to exist, establishing a puppet Emperor and effectively taking over the entire area for Japan.

This gave the Japanese a nice, remote, out-of-the-way place to carry out their experiments in biological warfare. The secret name Togo was given to the laboratory and the members assigned to the unit were first assigned to the Kwantung Army's Strategic Staff. Starting with a staff of about 300 Ishi's people developed a biological bomb and tested it, leading to an increase in his staffing to around 1,000 people

According to the book Unit 731: Japan's Secret Biological Warfare in World War II, 1989:

Detachment 731 was formed by command of the Emperor of Japan, Hirohito, issued in 1936. The Emperor's command was printed and copies of it were sent to all units of the Japanese Army for the information of all the officers."

In order to provide a cover for the operation, the group was called the "Epidemic Prevention and Water Supply Unit of the Kwantung Army." They did not even wear special uniforms for the unit, rather just wearing regular army clothing so anyone seeing them would think they were just regular Japanese troops.

The headquarters was Pingfan, a village in Manchuria. The facilities were rather plush by wartime standards. There were health facilities for the workers, a Shinto temple, restaurants, a school, a swimming pool, gardens, a library, athletic fields, etc. At its height Japan's bio-warfare groups employed some 20,000 people, counting military and civilians alike.

The organizational structure of Unit 731

The unit was expanded to about 3,000 men and was divided into eight sections:

1. First Division: bacteriological research, which included work with plague, anthrax, dysentery, typhoid, cholera and other diseases.

2. Second Division: warfare research and field experiments

3. Third Division: water filter production

4. Fourth Division: bacteria mass production and storage

5. Educational Division

6. Water Filter Division

7. Clinical Diagnosis Division

8. Supplies Division

Weapons and Targets

In order to develop an effective biological weapon, you needed to have the weapon itself and you also needed a way to deliver it. Dropping a bomb with bacteria in it would not work since the explosion and heat would destroy the bacteria. Work was done on producing fleas, infecting them with whatever germ was decided upon, and then finding a way to deliver the fleas alive to the target. This way the fleas could spread to rats and humans, carrying the disease and allowing it to keep infecting people well after the actual weapon was used.

In addition, targets were not just to be humans. Indeed plants themselves were considered targets, particular food plants. The Japanese were working to develop balloons that could carry infectious agents across the ocean, their target being the Pacific Northwest of the U.S. If it would work great panic could result along with major disruption of food production and distribution.

Of course, in order to produce a working biological weapon one must first test it on people to make sure that it works and that is exactly what Unit 731 did. They took prisoners which they termed "maruta (a Japanese word for "a log of wood"), the prisoners being taken from captured spies, Chinese soldiers, intellectuals, local workers, young boys, mothers and even pregnant women were all taken with the end result that about 3,000 of them died as a direct result of the experiments being performed upon them.

Here I will point out that a lot of the experiments that were done are things that were so utterly gruesome that I don't want to even discuss them here. If you really want to know, read the book.

According to the book A Plague Upon Humanity: The Secret Genocide of Ais Japan's Germ Warfare Operation, 2004

The experiments on humans were even recorded on film and shown to the officers of the Kwantung Army, to Tojo, Japanese prime minister and co-commander of Pacific theater operations for the Japanese military. A film made in July of 1940, showing germ bombs being loaded onto a plane bound for Ningho, was likewise shown to various officials, including Prince Takeda who was the Emperor's cousin, and Prince Mikasa, the Emperor's younger brother.

The entire project fell apart after the atomic bombs were dropped on Japan and Russia entered the war. The buildings were destroyed and the workers fled.

The Allied forces did not become fully aware of the danger until early 1944. A lot of secret work had been carried on by the Japanese, including the development of a jet plane that could have proven lethal to American air forces if it had been fully developed and produced in time. Fortunately, the Japanese and the Germans both mistimed their weapons programs, producing the deadliest weapons far too late to be of any practical use.

The U.S. is Targeted

There were plans drawn up for the use of biological weapons against U.S. troops in the Pacific Theater, and also for use against targets in India, Australia and Alaska, although none of this actually ended up being done.

Another scheme was to use one of the special Japanese submarines that carrying a plane and use the plane to spread bubonic plague on the city of San Diego. Another group of men in a small boat were to land and spread cholera and plague bacteria on particular targets. The plan ended up being canceled when someone finally realized that little military good would come of the attack and that all it would do would be to get the U.S. even angrier at Japan.

The Japanese did manage to get some balloons over to the U.S., but they did not have any bacteria on them. There were incendiary devices generally didn't work although the explosions were responsible for killing seven people.

A total of some 9000 balloons were launched starting around November of 1944, but only around 200 were spotted/found/brought down. The rest of the balloons probably ended up in the ocean. The balloons that did make the flight successfully got as far north as Canada and as far east as Michigan. The original concept was to use incendiary devices attached to the balloons to start forest fires and spread panic, but the devices just didn't end up working except in very rare instances. The balloons were not used for any biological warfare, however.

Rigid censorship by the government prevented people from finding out about the devices until the government finally admitted what was happening in May of 1945. Interestingly enough, Japanese newspapers reported that some 10,000 Americans were killed and forest fires and panic were both raging.

Who Knew?

The book also discusses just who knew about the work within the Japanese hierarchy, and that included most leading Army figures, probably the Foreign Ministry, and even the Emperor's brother who actually visited Unit 731 on one occasion. The Emperor's cousin held "executive responsibilities" over the unit and the Emperor's personal seal was used on orders forming the unit, although that does not prove that the Emperor himself actually knew. Someone could have used his seal that was authorized to do so or they might have illegally used it.

They weren't held accountable

What is very interesting about this is that, after the end of the war, the United States gave the top scientists in that group immunity from prosecution in exchange for the data they collected during the experiments which is not really something that is very morally defensible. It was done, basically, to try to prevent the Russians from finding out anything about the experiments, information that could come out at a war crimes trial if it were held.

There was a war crimes trial held in Russia in 1949, in which 12 Japanese bio-warfare officials were convicted, but the results were dismissed as false by MacArthur and by the government of the U.S., expanding the American cover-up of the Japanese activities.

The Joint Chiefs of Staff were the ones who ordered MacArthur to keep everything secret all in exchange for the information the U.S. got from the experiments that Unit 731 and its cohorts had performed.

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