Unit 731 (officially known as the Epidemic Prevention and Water Purification Department of the Kwantung Army, an army group of the Imperial Japanese Army) was a secret biological and chemical warfare research facility that conducted unethical/lethal experiments on humans during the Second Sino-Japanese War of World War II between 1937 and 1945. During this period, imperial Japan conducted what has been described as the Asian Holocaust, as it committed some of the most heinous war crimes ever.
History and Formation of Unit 731
The unit was the brainchild of the chief medical officer of the Japanese Army, Surgeon General Shiro Ishii. Ishii, who was born on the 25th of June 1892, in the Chiba Prefecture, studied medicine at Kyoto Imperial University before he was commissioned into the army in 1921. He joined as an army surgeon, second class (surgeon lieutenant) and was subsequently assigned to the 1st Army Hospital and Army Medical School in Tokyo. After a few years, Ishii went back to school for a post-graduate medical degree at his alma mater. He was noted by university staff for his odd practice of growing bacteria as pets rather than as research subjects.
Shiro Ishii was by 1925 promoted to an army surgeon, first class (surgeon captain). Through his position, he pushed for the creation of a bio-weapons program by the Imperial Japanese Army after having conducted research and a tour of the West, concluding that Western powers were creating their own programs. For this work, Army Minister Sadao Araki took a liking to Ishii and almost soon after promoted him to a senior army surgeon, third class (surgeon-major), in 1931.
A year after his promotion, Ishii was given the go-ahead to begin preliminary experiments on a secret bio-weapons program at the Zhongma Fortress prison camp. By 1935, he was promoted to a senior army surgeon, second class (surgeon lieutenant-colonel) and went on to set up a much larger facility outside the city of Harbin, China under the guise of work related to water purification. This was directed by a decree of Japanese Emperor Hirohito who authorized the unit’s expansion as well as its integration with the Kwantung Army.
By 1939, Unit 731 had become a huge attraction for medical professionals from Japan, as well as from China and Korea, due to its huge financial backing from the Imperial Army. Similar laboratories were further opened up in other Chinese cities; Beijing, Nanjing, Guangzhou, and Singapore, due to Japan’s control over the region with staff said to be in tens of thousands.
Experiments Carried Out On Humans
Unit 731 conducted its tests on a wide cross-section of human beings that included the elderly, infants, and even pregnant women. These people were either captured thieves or political prisoners although sometimes people were said to be just arrested on alleged suspicious activities for the main purpose of experimentation.
Some of the experiments conducted include vivisection; surgery to view and study the living internal structure of a person without the use of anesthesia which often resulted in the death of the victim. This was usually done to people purposely infected with venereal diseases in order to understand the effects of those diseases on the organs. Some of the other diseases tested include cholera, bubonic plague, smallpox, botulism, anthrax, and tularemia.
Other experiments carried out by the lab include frostbite testing, effects of flamethrowers and grenades based on distance to subject, the period of starvation that leads to death, and the effectiveness of high-pressure chambers, centrifuges, and temperatures.
Japanese Surrender and End of Unit 731
Following the surrender of Japan in World War II in August 1945 after the Hiroshima and Nagasaki bombings, Unit 731 had to abandon its work and return to Japan in order not to be captured by the Soviet Red Army. General Shiro Ishii had at this time ordered for the destruction of their work while further prohibiting other members to continue such research in mainland Japan.
The American Army had at this time occupied Japan and began investigating its biological warfare. Lieutenant Colonel Murray Sanders, a microbiologist and member of the U.S. military center for biological weapons, discovered the activities of Unit 731 and secretly granted immunity to physicians willing to share information on their work, including General Ishii.
Issues surrounding the activities of Unit 731 were never discussed publicly in Japan and somewhat remained a secret until the 1950s after the United States ended its occupation of Japan.