by Sophie Hammond
During the early twentieth century, the Imperial Japanese Army invaded and occupied Chinese lands without ever officially declaring war.
In 1915, Japan issued the secret Twenty-One Demands to Chinese president Yuan Shikai, with the intent to claim economic and political power over China. The Demands were divided into five groups, with the Group Five demands including concessions similar to those Japan had forced on Korea. After twenty-five rounds of negotiations and intense political maneuvering on President Yuan’s part, the Twenty-One Demands were agreed to, except for the Group Five demands. The other Demands, though, reinforced Japanese control of southern Manchuria, Shandong, and eastern inner Mongolia. Japan’s hold on Manchuria was especially strong. The Chinese warlord Zhang Zuolin tolerated Japan’s encroachments on his Manchurian territory in exchange for their help maintaining his power, and Japan controlled southern Manchuria economically through its ownership of most of Manchuria’s railway lines and its lease of the Liaodong Peninsula.
In 1928, a handful of extremist Japanese officers stationed in Manchuria bombed Zhang Zuolin’s personal train, assassinating him. According to many sources, they acted without any direct orders from Tokyo, hoping to provide Japan with an excuse to invade Manchuria. Whether or not the Imperial Japanese Army actually authorized the assassination, Zhang Zuolin’s son and heir Zhang Xueliang was understandably not eager to ally himself with the Japanese after this. Instead, he gave his loyalty to the Nationalists, led by Chiang Kai-shek, who took as their main goal resistance to foreign influence in China.
The Manchurian railways also became a source of major contention, and to circumvent Japanese power in the region, the Chinese began building their own railway system which bypassed Japanese lines. It was these railways which formed the pretext for the Mukden Incident. Increasing tensions in the summer of 1931 culminated in the explosion of a bomb which destroyed a section of Japan-owned railway tracks near the city of Mukden. Japan blamed the Nationalists for the bomb, although even the League of Nations, after a thorough investigation, believed that the bomb had actually been planted by mid-level Imperial Japanese Army officers to justify seizing Manchuria.
The Mukden Incident, whether or not it was a staged pretext, is considered the beginning of Japan’s full-scale invasion of Manchuria and the beginning of Japan’s Fifteen Years’ War. By the next year, Japan had made Manchuria into Manchukuo, a puppet state headed by a puppet leader, the deposed Qing emperor Pu Yi. Pu Yi had become emperor of China in 1908 at the age of two, only for China to become a republic three years later. He lived in powerless luxury until 1924, when political turmoil in China caused him to appeal to Japan for protection. Eight years later, Japan made him Emperor of Manchukuo, and he lived again in powerless luxury.
As Japan pushed further and further into China and tightened its control over the regions it occupied, Chinese communist and Nationalist forces continued to fight against each other. However, in 1936, Zhang Xueliang, the leader of the Nationalists in Manchuria under Chiang Kai-shek’s command, forced Chiang to stop the civil war and ally with the communists to oppose the Japanese. Zhang achieved this unexpected result by kidnapping Chiang in Xi’an after Chiang arrived to order Zhang to resume fighting the communists. Chiang agreed to Zhang’s demands after communist leader Zhou Enlai intervened in the negotiations and helped persuade Chiang to fight more actively against the Japanese and to allow the communists local authority.
The Xi’an Incident of 1936 helped speed China on its way to a full-scale resistance to Japanese expansion, but most historians point to an incident at the Marco Polo Bridge near Beijing as the real beginning of the United Front against the Japanese. On the night of July 7, 1937, a small Japanese force demanded to be allowed into the walled town of Wanping to find a missing Japanese soldier. The Chinese garrison refused, and during the argument, a shot rang out. It remains a mystery which side fired the first shot, but soon enough, both sides began firing.
The clash at the Marco Polo Bridge bolstered Chinese resistance. Immediately, nearly all of the regional political and military groups in China threw their weight behind the Nationalists, even those who had formerly withheld their support. In September of that year, the Communists agreed to put their troops under Nationalist governmental control. This quickly escalated the fighting between Chinese and Japanese troops, as the Japanese seized several major Chinese cities and ports, including Shanghai in a three-month siege, followed by the unrestrained assault on the Nationalist capital, Nanjing, in what has become known as the Rape of Nanking. The Rape of Nanking further intensified Chinese resistance, and while the Imperial Japanese Army continued to expand their control over parts of China, their progress was stymied outside urban areas.
Yet war remained officially undeclared by either side until December 9, 1941, when the United States and China simultaneously declared war on Japan after the attack on Pearl Harbor.
Cavendish, Richard. “Pu Yi, Last Emperor of China, Is Pardoned.” History Today, vol. 59, no. 12, Dec. 2009.
The Editors of Encyclopædia Britannica. “Second Sino-Japanese War.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 23 Dec. 2017, www.britannica.com/event/Second-Sino-Japanese-War.
The Editors of Encyclopædia Britannica. “Zhang Zuolin.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 31 May 2018, www.britannica.com/biography/Zhang-Zuolin.
The Editors of Encyclopædia Britannica. “Marco Polo Bridge Incident.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 30 June 2018, www.britannica.com/event/Marco-Polo-Bridge-Incident.
Huang, Yanzhong. “China, Japan and the Twenty-One Demands.” Forbes, Forbes Magazine, 21 Jan. 2015, www.forbes.com/sites/yanzhonghuang/2015/01/21/china-japan-and-the-twenty-one-demands/.
“Invasion of Manchuria and Japanese Aggression.” The Pacific Theater, Lynden Pioneer Museum, 3 June 2014, lyndenpacifictheater.wordpress.com/china-invasion/.
The Office of the Historian, Bureau of Public Affairs. “The Mukden Incident of 1931 and the Stimson Doctrine.” Milestones in the History of U.S. Foreign Relations, U.S. Department of State, history.state.gov/milestones/1921-1936/mukden-incident.
Overy, Richard. “China’s War with Japan, 1937-1945: The Struggle for Survival by Rana Mitter – Review.” The Guardian, Guardian News and Media, 6 June 2013, www.theguardian.com/books/2013/jun/06/china-war-japan-rana-mitter-review.
Roosevelt, Franklin D. “On the Declaration of War with Japan - December 9, 1941.” Franklin D. Roosevelt Presidential Library and Museum, Marist College, docs.fdrlibrary.marist.edu/120941.html.
Twitchett, Dennis C., et al. “China.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 10 July 2018, www.britannica.com/place/China/War-between-Nationalists-and-communists.
von Stauffenberg, Claus. “World War II: China's Declaration of War Against Japan, Germany and Italy.” Jewish Virtual Library, American-Israeli Cooperative Enterprise, www.jewishvirtuallibrary.org/china-s-declaration-of-war-against-japan-germany-and-italy-december-1941.
Wright, Edmund, editor. A Dictionary of World History. 2nd ed., Oxford University Press, 2006
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The Flying Tigers, officially known as the First American Volunteer Group, were American pilots who fought in the Chinese Air Force during World War II between 1941 and 1942. They are best known for popularizing the shark’s-mouth design frequently painted American military aircraft. In addition, their now-famous unit insignia of a winged Bengal tiger was designed by the Walt Disney Company.
The commanding officer of the Flying Tigers, Claire L. Chennault, was a retired captain from the Army Air Corps who was working in China as an advisor to the Chinese Air Force when the Second Sino-Japanese War broke out in 1937. The Chinese Generalissimo Chiang Kai-Shek quickly hired Chennault to lead the training of Chinese fighter pilots.
Chennault was able to resist Japanese attacks for two years with planes donated from the Soviet Union, but at last in 1939 Japanese forces overwhelmed Chinese defenses and destroyed most of the Chinese Air Force. In 1940 Chennault traveled to Washington, D.C. to buy aircraft and recruit pilots to fight for the Chinese. Realizing the potential dangers of China being defeated by the Japanese, President Roosevelt agreed to allow American pilots to resign from the military in order to go serve in the Chinese Air Force—at this point the United States had not officially entered the war against the Japanese and wanted to maintain an appearance of neutrality.
Lured by the promise of better pay, ninety-nine pilots and one hundred eighty four support troops sailed to Burma, where they arrived in the middle of the monsoon season and were forced assemble their own aircraft before beginning training. Imitating a British Royal Air Force design, the volunteers painted shark’s mouths on their aircraft to make them more threatening. This was not known to their supporters in Washington, who gave them the nickname the Flying Tigers in the spring of 1941.
Over the next few months, Chennault put his men through highly realistic combat training, which resulted in multiple accidents and fatalities, but ultimately prepared the pilots for the stress of combat. Chennault trained his men to avoid one-on-one dogfights and plan their attacks in pairs, and also prepared them to face Japanese maneuvers, which he had learned between 1937 and 1939.
The Flying Tigers were divided into three squadrons and a headquarters unit composed of support staff. The squadron’s were the Adam and Eve squadron, led by Robert Sandell, the Panda Bears, led by Jack Newkirk, and the Hell’s Angels, led by Arvid Olson. In addition, they received extensive help from the native Chinese who helped house the men, construct and store the planes, rescue downed pilots, and provide early warning against Japanese attacks.
On December 7, 1941, Japan attacked Pearl Harbor and simultaneously destroyed most of the United States’ forces in the Philippines. In an attempt to seize control of the only land route for goods traveling to China, Japan invaded Burma, and raided the city of Rangoon. The Hell’s Angels squadron of the Flying Tigers fought alongside the British Royal Air Force for months in defense of the city, and was eventually relieved by the Panda Bears squadron. The Hell’s Angels and Adam and Eve squadrons retreated into China, where they continued to launch attacks throughout 1942 against Japanese ground forces and airfields as the invading forces took control of Burma and prepared an attack on Southeast China.
The famous Flying Tiger unit insignia was designed around this time as well. In the spring of 1942, Roy Williams, an artist for Walt Disney Studios, created the image of a cartoon winged Bengal tiger flying in a blue ‘V’ for the Flying Tigers. The design was used by the group after they were incorporated into the United States Army, and similar designs are still in use today in the Air Force.
Thanks to the Flying Tigers’ defense, the Japanese were unable to successfully invade China, and over the next two years the United States was able to defeat the Japanese army and liberate the region. The Flying Tigers continued to fight until July 4th, 1942 they were absorbed into the American Army Air Forces and renamed the 23rd Fighter Group. In theory, most pilots were to continue fighting, but in reality most left China and returned to the United States. Those who did remain in China, such as Tex Hill continued their missions against the Japanese, while many who returned home eventually returned to combat as pilots in other services, most notably Jim Howard and Greg Boyington, who were awarded Medals of Honor. Chennault himself remained in China, first as the commanding officer of the China Air Task Force, then as a major general in charge of the Fourteenth Air Force. He eventually retired in 1945.
During their short existence, the Flying Tigers only lost twelve planes and ten pilots in battle, while destroying almost three hundred Japanese aircraft. Even though they were always outnumbered, the Tigers were able to put up a strong resistance to the attacking Japanese, inflicting heavy casualties and slowing down the invasion. Without the resistance of the Flying Tigers and the British Royal Air Force, the Japanese Imperial Army would have swept through Burma and possibly been able to successfully establish a foothold in China. Despite their eventual defeat in and withdrawal from Burma, the Flying Tigers’ delay of the advancing Japanese was crucial to the Allied war effort.
Eisel, Braxton. The Flying Tigers: Chennault's American Volunteer Group in China. Washington, D.C.: Air Force History and Museums Program, 2009. https://permanent.access.gpo.gov/gpo66524/AFD-101028-007.pdf.
Elder, Robert. "American Volunteer Group (AVG)." In Encyclopedia of Chinese-American Relations, edited by Yuwu Song. McFarland, 2009. http://libproxy.lib.unc.edu/login?url=https://search.credoreference.com/content/entry/mcfcham/american_volunteer_group_avg/0?institutionId=1724
Ference, Greg. "Chennault, Claire L. 1893-1958." In Encyclopedia of Chinese-American Relations, edited by Yuwu Song. McFarland, 2009. http://libproxy.lib.unc.edu/login?url=https://search.credoreference.com/content/entry/mcfcham/chennault_claire_l_1893_1958/0?institutionId=1724
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by Sophie Hammond
Unit 731 was the administrative center of the top secret biological warfare project of the Imperial Japanese Army. Located in rural Manchuria, at that time a puppet state of Japan, and known by the codename “the Epidemic Prevention and Water Purification Department”, Unit 731’s purpose was, in fact, to cause epidemics and contaminated water—for the enemy. The Imperial Japanese Army was fighting multiple wars and needed to win all of them. To do so, they turned to biological warfare.
The Geneva Protocol of 1925 banned biological and chemical warfare in international armed conflicts in order to prevent the outbreak of another war on the magnitude of World War I. The Japanese delegation in attendance at the conference had signed the agreement, but since the Japanese Diet did not ratify the agreement, Japan was not bound by the Geneva Protocol. Several countries who had ostensibly agreed to the Protocol were developing their own weapons in secret, and Japan was no exception.
The human test subjects of Unit 731 were criminals, political prisoners, Communists, or civilians—usually pregnant women, children, and the elderly—who were considered useful for experiments and were rounded up under trumped-up charges. Seventy percent of these victims were Chinese, while others were Korean, Mongolian, and Russian, and a few might have been Allied prisoners of war. They were called marutas by the researchers, or “logs”, because the local Manchurians were told that the facility was a lumber mill. Research findings discovered at Unit 731 were occasionally published in peer-reviewed scientific journals, where the articles claimed the experiments had been performed on Manchurian monkeys.
Whether these prisoners were called logs or monkeys, their human suffering was immense. One of the most common experiments at Unit 731 was the vivisection of diseased bodies. Researchers found the most virulent strains of disease by infecting prisoners, usually by injecting them with “vaccines” or feeding them contaminated food, and killing those prisoners who recovered quickly from their illnesses. They then injected the more potent bacteria and viruses from the sickest prisoners into the next “generation” of victims. For researchers who wanted to view a more natural progression of disease, some prisoners were kept locked in cages in the same room as plague-infested mice and fleas to see how long it took for them to become infected. The prisoners were then sliced open so that researchers could see how the disease affected living organs. This vivisection was done without anesthetic, to ensure results untainted by any external factors. Vivisections were also commonly performed on pregnant women—many of whom were pregnant by rape.
The researchers were especially interested in the pregnancies of women with syphilis. The Japanese military was struggling to combat the syphilis sweeping through its ranks, likely due to the rape of civilian women and of the comfort women forced to service the military. At first the researchers tried to inject prisoners with syphilis, but seeing that this yielded few results, they turned to raping them. Two prisoners, one infected with syphilis, were placed in a room together along with armed guards and made to have sex with each other. Once the previously healthy partner contracted syphilis, they would be inspected periodically to see the progression of the disease, culminating in a vivisection to see what syphilis did to the organs and—in the case of pregnant prisoners—the baby. Vivisection was practiced on Chinese citizens at many other government-sponsored research facilities besides Unit 731. For a time, it was considered the most effective way to train young Japanese medical students to perform surgeries correctly.
Unit 731 researchers also experimented with methods of treating frostbite. Prisoners were taken outside in freezing weather, sometimes after being dipped in water, and kept there until their limbs were frozen solid. Artificial cool air currents accelerated the freezing. A Japanese officer who watched one of these experiments stated later that frostbite was considered achieved if, when struck, the prisoner’s limbs made a sound like a wooden board. Sometimes prisoners were left to thaw, their arms and legs turning gangrenous until they rotted. Usually, however, frostbite victims were immersed in water at various temperatures to see which temperatures cured frostbite the fastest. It’s from these tests run by Unit 731 that the world knows the most effective way to deal with frostbite—not to rub the affected limbs, but to immerse them in water between 100 and 122 degrees Fahrenheit.
But the main research aim of Unit 731 was to develop the most effective biological warfare weapons. At a testing ground called Anda, prisoners were lashed to stakes and suffocated with poison gas or forced to wait while planes dropped plague bombs—bombs full of plague-infested fleas—over them. Prisoners were also used to test the effective range of flamethrowers, chemical weapons, and bombs, including bacteriological bombs. The resulting shrapnel of these weapons was often infected with various diseases, so that researchers could discover how long it would take people to die from being hit by flying shrapnel only. Unit 731 helped develop balloon bombs, which were sent to float across the Pacific to the United States and cause destruction and terror. Only a few ever actually arrived in the United States and went off, and while American news outlets were requested not to report on these bombs for fear of causing mass hysteria, there were at least seven verified American victims.
Unit 731 was also instrumental in planning an army operation which was never carried out, Cherry Blossoms at Night, which involved infecting San Diego with the bubonic plague using kamikaze pilots. This operation was halted in large part, it seems, by the intervention of Hideki Tojo—a man the United States later hanged for his other war crimes. Other contributing factors to the failure of Cherry Blossoms at Night were the Japanese surrender in August 1945 (Cherry Blossoms at Night was planned for September) and the necessity near the end of the war for the Japanese to focus on defense rather than offense.
China wasn’t so lucky. Using knowledge developed from Unit 731 tests, the Imperial Japanese Army created plague bombs and had airplanes spray diseases like bubonic plague, cholera, and anthrax over Chinese cities, killing hundreds of thousands of people. Plague outbreaks, for example, were reported in Changde in north-central China and Ningbo in eastern China. Between three and four hundred thousand Chinese people are estimated to have been killed by this method of biological warfare.
Unit 731’s other experiments included injecting prisoners with animal blood and horse urine, heating them until they died, spinning them with centrifuges until they died, and locking them in pressure chambers until their eyes popped out. It’s estimated that about 3,000 people died from the tortures they underwent at Unit 731.
After the war, the American government helped cover up many of the atrocities the Japanese military committed during the war. The masterminds of Unit 731 were granted immunity during the Tokyo Trials in exchange for handing over what data existed on the Unit 731 experiments. Many of those affiliated with Unit 731 enjoyed long and illustrious medical careers. Three Unit 731 researchers became the president of the Japan Medical Association, the head of the Japan Olympic Committee, and the Governor of Tokyo.
In April 2018, a nearly complete list of the 3,607 people who were employed by Unit 731 on January 1, 1945 was released to the public. Katsuo Nishiyama, professor emeritus of Shiga University of Medical Science, is attempting to use the list to declare the university degree of one of Unit 731’s officers illegitimate. It seems likely the experiments which this man oversaw for his dissertation were performed on Unit 731 prisoners, rather than on animals as he had claimed. Many hope that the release of this list will be a major step towards Japan openly condemning its wartime atrocities.
For more information about Unit 731, please check out some of the sources used to write this article. Additionally, Pacific Atrocities Education has produced a book about Unit 731. You can view it here: http://www.pacificatrocities.org/unit-731-ebook.html
Brennan, David. “Identities of Japanese War Crimes Unit That Killed POWs Released.” Newsweek, 17 Apr. 2018, www.newsweek.com/identities-japanese-war-crimes-unit-killed-pows-released-889544.
Harris, Sheldon H. Factories of Death: Japanese Biological Warfare, 1932-1945 and the American Cover-Up. Routledge, 2002.
Kristof, Nicholas D. “Unmasking Horror — A Special Report.; Japan Confronting Gruesome War Atrocity.” The New York Times, The New York Times, 17 Mar. 1995, www.nytimes.com/1995/03/17/world/unmasking-horror-a-special-report-japan-confronting-gruesome-war-atrocity.html.
Park, Eun. Theodicy--Through the Case of "Unit 731". Boston University, Dec. 2003, people.bu.edu/wwildman/WeirdWildWeb/courses/thth/projects/thth_projects_2003_parkeun.htm.
Pawlowicz, Rachel, and Walter E. Grunden. “Teaching Atrocities: The Holocaust and Unit 731 in the Secondary School Curriculum.” The History Teacher, vol. 48, no. 2, Feb. 2015, pp. 271–294., www.societyforhistoryeducation.org/F15Preview.html.
Reuters, Jason Lee. “Chinese Man Looks at Figures Showing Vivisection Tests at Exhibition Hall of Historical Japanese Germ Warfare Located in South of Harbin.” Newsweek, 17 Apr. 2018, www.newsweek.com/identities-japanese-war-crimes-unit-killed-pows-released-889544.
Weeks, Linton. “Beware of Japanese Balloon Bombs.” NPR History Department, National Public Radio, 20 Jan. 2015, www.npr.org/sections/npr-history-dept/2015/01/20/375820191/beware-of-japanese-balloon-bombs.
Williams, Peter, and David Wallace. Unit 731: The Japanese Army's Secret of Secrets. London, 1989.
Unit 731 was known as a covert chemical and biological warfare research and development section of the Imperial Japanese Army that commenced lethal human experimentation during the World War 2. This program was responsible for some of the most horrific war crimes that were carried out by the Imperial Japanese Army.
Officially it was known as the Epidemic Prevention and Water Purification Department of The Kwantung Army, the site was originally set up under the command of General Shiro Ishii who was a combat medic officer at the Kwantung Army. He finished his studies in microbiology at the Kyoto Imperial University in Japan. He came up with the idea of having the facility built to keep up with the West, since they were believed to be developing their own weapons of biological warfare. The Japanese government heavily invested in the facility in order for it to function fully. General Shiro Ishii’s career started accelerating in 1932 after he was chosen to be the head of the biological warfare division where his mission was to perform covert experiments on live subjects. The location was later than moved to Pingfang and General Ishii was again appointed as the director.
Masaji Kitano was a commanding officer of Unit 731. He graduated as a medical doctor at Tokyo Imperial University. He joined the army as an army surgeon with the rank of a lieutenant. Right before the full blown Sino-Japanese War, he taught microbiology at the Manchu School of Medicine in Manchuria. Manchuria had been a puppet state of Japan’s since 1931. Read more here: http://www.pacificatrocities.org/blog/marutas-in-manchuria-imperial-japanese-biological-warfare-1931-1945
By 1942, he was made second in command of Unit 731. He was known to be the chief funeral commissioner of Shiro Ishii.
After the Japanese surrendered in August 1945, he ended up being detained in a POW camp in Shanghai. Due to a deal made with the Allied, he was released in exchange for research material of biological warfare. He was later repatriated to Japan in January 1946 and became the chief director of Green Cross, a Japanese Pharmaceutical company.
Another member of the Unit 731 was Yoshimura Hisato, who was a physiologist. Before his career in Unit 731 in 1938, he was a lecturer at Kyoto Imperial University Faculty of Medicine. He was employed by the Imperial Japanese Army as an Army Engineer, which was a researcher who was treated like an officer but not a professional military serviceperson. At Unit 731, he took a great interest in hypothermia. Taking into consideration Maruta’s study in limbs, Hisato made his prisoners submerge their limbs in a tub of water that was filled with ice and then had them hold until their leg or arm had frozen solid and a coat of ice formed in their skin. An eyewitness stated that the limb sounded like wood when they were struck with a cane. In addition the physiologist also tried different methods for rapid rewarming of the frozen appendages by dousing them in hot water, holding them close to an open fire source or even leaving the subjects all night in order for him to see how long it would take for an individual’s own blood to thaw out.
After the war was over, he was able to obtain war crime immunity, and he became the president of Kyoto Prefectural University of Medicine.
In addition, Yasuji Kaneko is also one of the alleged members of the Unit 731 as the testimony of his crimes committed have appeared in the 2001 film known as Japanese Devils and 2007 film Iris Chang: The Rape of Nanking. He started testifying at the age of 76 in 1996 about his activities in Nanjing Massacre as well as Unit 731. As an ex-soldier of the Imperial Japanese Army, not only did he spread cholera into the water system in Linqing in 1943. He had also claimed to raped many women during the war as he could not afford comfort woman as a lower ranking soldier.
Yoshio Shinozuka was a teenager when he joined Unit 731 under the impression to provide safe drinking water to other soldiers. His day to day duty included raising fleas infected with plague on rats as well as vivisections.
There were many victims from Unit 731, but many of the soldiers were able to be freed in exchange for their knowledge of human experimentation. Many of them lived prosperous lives after the war. Although they gained a lot of science knowledge, their ways of violating human rights were mostly forgiven in the name of science.
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by Danielle Dybbro
In a previous blog post I wrote about Unit 731, but the facility in Harbin was not the only Imperial Japanese facility used for biological warfare research.
General Shiro Ishii was the head of the Imperial Japanese biological warfare research program. Ishii made extensive visits to Europe in order to tour military hospitals during the mid 1920s, but the main reason for his European tour was to investigate biological warfare research. Ishii studied the research that was developed during World War I, which later heavily influenced his creation of Unit 731. Additionally, on his world tour, some of the countries he visited were secretly researching biological warfare, and a Military Attaché in the Japanese Embassy in Washington D.C. “said that he heard that Ishii had studied bacteriological warfare at the Massachusetts Institute of Technology in Boston.” Upon his return to Japan in 1930, he managed to convince the Japanese State Department of Military Affairs to develop a biological weapons program.
The invasion of Manchuria in 1931 by the Japanese was the golden opportunity that General Ishii had been waiting for. The wide expanses of uninhabited land served as the perfect arena for conducting biological warfare research, as the small island nation of Japan had severely limited research potential because of the issues of space and safety. By 1933 Ishii had established facilities in Manchuria for conducting both defensive and offensive biological warfare research. Defensive research involved the production of vaccines and offensive research was the main focus of the notorious Unit 731 for the purpose of developing diseases for use as weapons, including plague, glanders, anthrax, and typhus. World War II began in 1939 for the Western world, but by this time there were an estimated 18 other biological warfare facilities scattered throughout the Japanese empire, from Manchuria in the north to Indonesia in the south.
In the use of human subjects, researchers would refer to the subjects as ‘marutas’ which translated to ‘wooden logs.’ By dehumanizing the Chinese, Russian, Mongolian, and Communists that were rounded up by the Japanese secret police, the Kempeitai, researchers could justify the harsh treatment of marutas in their experiments. In a testimony, Yoshio Shinuzaka confirmed this practice and said that, “We called the victims ‘logs’… We didn't want to think of them as people. We didn't want to admit that we were taking lives. So we convinced ourselves that what we were doing was like cutting down a tree. When you see someone in that state, you just can't move. Your mind goes blank. The fear is overwhelming.”
Evidence of biological attacks in China are recorded in official records of a number of Japanese military officers, including field tests in Chinese villages leading to outbreaks of cholera and the plague. At Unit 731, bombs with fleas infected with the plague, shrapnel carrying anthrax, and planes spraying other diseases were tested on prisoners. Prisoners would be tied to stakes and the bombs would be dropped at varying distances and their bodies were monitored for reactions, which often involved cutting subjects open without anesthetic. After death, their organs would be preserved for further study.
South of Harbin, where Unit 731 was located, was the city of Changchun, which was chosen as the capital for the Manchurian puppet state. In 1936 the Anti-Epizootic Protection of Horses Unit was created in Changchun, which later became known as Unit 100. Unit 100 was not run by Ishii, but by Major Yujiro, a veterinarian who sometimes cooperated with Ishii in joint research. This unit specialized in the prevention of animal diseases, but also researched plant and animal biological warfare akin to Unit 731’s activities. The unit’s focus was on sabotage operations, with research conducted for the cultivation of crop viruses and livestock diseases. Both people and animals were subjected to experimentation, and a number of recorded testimonies from former workers and medical students describe seeing dead bodies being wheeled away from operating rooms and animals being poisoned with contaminated crops. In Soviet-sponsored war trials, a former Unit 100 worker confirmed that he had “taken part in these inhuman experiments on living people, in bacteriological sabotage and in the preparations for bacteriological warfare against the Soviet Union,” and other admissions of guilt are found throughout the trial transcript.
According to some scholarship, the United States government struck a plea bargain with General Ishii in exchange for all the medical research acquired from the experiments conducted at Unit 731. In a letter written in 1998, the Director of the Department of Justice’s Office of Special Investigations in Los Angeles confirmed that the exchange occurred: “Two of these [formerly classified] reports [about biological warfare data collected by the Japanese and the arrangement made between the United States and Lieutenant General Shiro Ishii, the Commander of the Unit 731], dated November 17, 1981 and May 5, 1982, confirm that Ishii and his colleagues received immunity from prosecution and that, in exchange, they provided a great deal of information to U.S. authorities.” In contrast, in memo dated from 1995 from the Department of the Army, Edward Drea, then the Chief of the Research and Analysis Division of Military History, claims that “there is no primary source material guaranteeing General Ishii immunity from prosecution. He was not tried as a war criminal apparently in order to conceal from the Soviet Union the extent of the information he provided the United States about biological warfare. Even that interpretation, however, rests on very fragmentary evidence.”
However, in 1995 in another primary government source, an internal memo claims that with the emergence of the Cold War, the Americans felt that they could not entrust the biological warfare information amassed by the Japanese to the Soviets. In order to keep the research from falling into Soviet hands, the documents handed over to the United States in 1945 were classified and thus were not able to be used as evidence in the Tokyo War Crimes Trials. Despite this cover up, the Soviet Union tried twelve of them in 1949 in the Khabarovsk Trials, which are available to read online through Google books.
Unfortunately, the United States “dismissed the verdicts [in the Khabarovsk trials] with the evidence as another in a series of long-running Stalinist show trials.” Additionally, though 12 Japanese officers involved with Unit 731 were tried in Khabarovsk, the convicts received prison sentences ranging from 2-25 years and most were freed in the 1950s. This is in stark contrast to the Nuremburg and Tokyo war crime trials, which resulted in German and Japanese officials being hanged or sentenced to life in prison.
Scholarship on Japan’s biological warfare program has been increasing since the 1980s with admissions of guilt by former Unit 731 workers and the discovery of a cache of forgotten military records in a Tokyo bookstore in 1984, but the issue is that the evidence is scattered and often fragmentary in nature. Historians must continue to piece together the narrative and bring to light a fuller picture of Imperial Japan’s biological warfare research that began well before the outbreak of World War II.
Cunliffe, William H. “Nazi War Crimes and Japanese Imperial Government Records: Select Documents on Japanese War Crimes and Japanese Biological Warfare, 1934-2006.” Interagency Working Group.
Drea, Edward; Bradsher, Greg; Hanyok, Robert; Lide, James; Petersen, Michael, & Daqing Yang. Researching Japanese War Crimes: Introductory Essays. Washington, D.C.: Nazi War Crimes and Japanese Imperial Government Records Interagency Working Group, 2006.
Harris, Sheldon. Factories of Death: Japanese Biological Warfare, 1932-45, and the American Cover-up. New York: Routledge Press, 1994.
“Japanese Biological Warfare Experiments in World War II,” NSC Contingency Press Guidance. U.S. Internal Memo, August 16, 1995.
Letter, December 17, 1998. Headed “Re: U.S. Non-prosecution of Japanese War Criminals,” sent to the associate dean of the Simon Wiesenthal Center, Los Angeles. Quoted in Reynolds, Gary. “U.S. Prisoners of War and Civilian American Citizens Captured and Interned by Japan in World War II: The Issue of Compensation.” Congressional Research Service Report for Congress, The Library of Congress. Updated 2002. 22.
Pawlowicz, Rachel and Grunden, Walter. “Teaching Atrocities: The Holocaust and Unit 731 in Secondary School Curriculum.” History Teacher, Vol. 48 Issue 2, p. 271-294, February 2015.
Talmadge, Eric, “Japanese Soldier Faces the Poison of His Past,” Los Angeles Times, September 19, 2004.
Tsuchiya, Takashi. “The Imperial Japanese Medical Atrocities and its Enduring Legacy in Japanese Research Ethics.” Abridged from chapter “The Imperial Japanese Experiments in China” in Oxford Textbook of Clinical Research Ethics, 2008.
Tsuneishi & Asano, Suicide of Two Physicians, 48. Quoted in Harris, Sheldon. Factories of Death: Japanese biological warfare 1932-45 and the American cover-up, 19.
Tyson, James. “Proof found of Japanese gas, germ tests on POWs.” United Press International, August 16, 1984.
Working, Russell. “The trial of Unit 731.” Japan Times, June 5, 2001.
Yamada, Otozo. Materials on the trial of former servicemen of the Japanese Army, charged with manufacturing and employing bacteriological weapon. Moscow: Foreign Languages Pub. House, 1950. Accessed via Google Books.
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by Mark Witzke
In the late 19th century, as China declined in the face of internal struggles and foreign intrusion, Japan was on the rise. As the world moved on to the 20th century, China’s loss of influence over Korea and the stunning victory of Japan in the Sino-Japanese War confirmed that China was no longer the premier power in the Pacific. With this victory, Japan, the former tributary state to the Chinese Empire, followed the example set by the Western powers and claimed territory from China. They forced China to sign another humiliating unequal treaty (Treaty of Shimonoseki 1895), which ceded Taiwan, the Penghu islands, and the Liaodong Peninsula to the Japanese Empire. This was the beginning, but far from the end of Japanese conquest in China. This conquest would eventually become one of the most destructive conflicts in world history, engulfing China in a storm of chaos and destruction and causing the deaths of millions and the loss of much of China’s territory.
Description: military actions taken in the 1st Sino-Japanese War
In the years following the 1st Sino-Japanese War, China continued to be weakened by internal instability. The fall of the Qing Empire in 1911 was soon followed by the Warlord Era, a time where a central authority in China barely existed. Eventually, beginning in 1926, Chiang Kai-Shek led both the Guomindang (GMD) and the Chinese Communist Party (CCP) on the Northern Expedition, which restored some resemblance of order. However, his betrayal of the Communists soon after in 1927 during the Shanghai Massacre ensured that a fully united government had no hope of continuing. As the two Chinese parties struggled, Japan saw its chance for conquest and in the 1931 Mukden Incident created a staged explosion as a pretext to invade Manchuria and establish a puppet regime, naming it Manchukuo. At this point, Chiang Kai-Shek, the ruler of most of China, felt the military was too weak to effectively resist Japan and instead continued to fight the Communists, hoping to gain strength and eventually fight off the Japanese. However, with the loss of Manchuria the Japanese now dominated much of China’s northeastern territory. Although the conflict ended with a truce, the GMD refused to recognize Manchukuo as a legitimate state.
In the years following from 1931-1937, guerilla warfare and skirmishes were common but much of the GMD’s troops and resources were allocated towards fighting Communists rather than Japanese. In the south of China, the GMD fought to eliminate the CCP once and for all and began to encircle the last of the Communist territories. The CCP broke out from this containment in late 1934 and began an epic retreat to the northwest of China in Shaanxi. This “Long March” saved the Communist party and consolidated Mao Zedong’s role as the undisputed leader of the CCP. In 1936, the Xi’an incident led to the capture of Chiang Kai-Shek and forced him to once again form a United Front with the Communists. The GMD and Communists prepared for war and it would soon arrive.
The Marco Polo Bridge Incident began as misunderstanding followed by a small exchange of fire. Although both units’ commanders apologized, reinforcements were called in for both sides, tensions escalated and within a week the war had begun in earnest. Hundreds of thousands of Japanese flowed into northern China, quickly pushing the Nationalist forces back and leaving only Communist guerilla insurgencies remaining. Beijing and Tianjin soon fell to the Japanese armies and the Japanese continued marching southward. Although the GMD took a determined stand with its most well-trained and equipped army divisions in the defense of Shanghai, that city too soon fell to the onslaught of the Japanese military. The Japanese continued on slaughtering and pillaging as they went, including the horrific Nanjing Massacre. By the beginning of 1938 Japan had extended its territory from the north of China into Shanghai, Nanjing, Xuzhou, Wuhan and vast areas of the middle and coastal areas of China.
Description: Japanese troops march through Beijing, August 13, 1937
The Japanese had soundly defeated the GMD and the CCP forces and conquered many of China’s most populous and industrious cities. The GMD was forced to flee to the southwest of China and establish a headquarters in Chongqing while the CCP hid in Shaanxi and conducted guerrilla warfare behind Japanese enemy lines. As 1938 turned to 1939, the Japanese advance slowed and this Sino-Japanese conflict became part of an even greater one—World War II. The remains of Free China held out against sustained bombing campaigns as it hoped to outlast Japan. In this chaotic time, world politics was in flux and soon China would find itself a member of the Allies, joining with Britain, the Soviet Union, and later, the United States against Japan, Germany, and Italy.
Description: Japanese occupation of China by 1940
Stuck in a stalemate on the Chinese mainland, Japan turned towards the seas and moved its fleet out, conquering islands and spreading throughout the Pacific. During this time Japan also consolidated their gains in the south of China, taking both Chinese and foreign administered cities; including, Canton, Xiamen, and Hong Kong. The GMD and CCP were both ineffective in their counterattacks while shock and awe campaigns in southern China killed thousands and reduced buildings to rubble. In CCP infiltrated areas, Japan carried out the “three-alls policy” a campaign of “Kill all, burn all, loot all”. Villagers throughout China were slaughtered, their food stolen, and their homes burned to the ground.
By 1942 the Japanese Empire had reached its greatest extent. It dominated the northern cities of China, controlled the puppet state of Manchuria, administered Taiwan, and ruled the prosperous southern port cities. Japan had possession of roughly 25% of China’s enormous territory and more than a third of its entire population. Beyond its areas of direct control, Japan carried out bombing campaigns, looting, massacres and raids deep into Chinese territory. Almost no place was beyond the reach of Japanese intrusion. However, at this peak the tide began to turn. Despite the death and destruction, Japan in the end could not defeat the last of Chinese resistance. Meanwhile, although the British had failed to effectively defend Hong Kong, Singapore and Burma, as the United States entered the War in the Pacific, Japan began to know defeat and eventually was on the run. After many years of struggle and hardships, all of China would soon be free of Japanese rule.
Description: Furthest extend of Japanese occupation in China at the end of World War II
Description: Furthest extend of Japanese occupation in China at the end of World War II
Holcombe, Charles. A History of East Asia: From the Origins of Civilization to the Twenty-first Century. Cambridge, United Kingdom: Cambridge UP, 2017. Print.
Kissinger, Henry. On China. New York: Penguin, 2012. Print.
Spence, Jonathan D. The Search for Modern China. New York: Norton, 1990. Print.
Taylor, Jay. The Generalissimo: Chiang Kai-shek and the Struggle for Modern China. Cambridge, MA: Belknap of Harvard UP, 2011. Print.
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by Danielle Dybbro
The systematic medical experimentation of Chinese, Korean, Mongolian, and Allied prisoners during World War II was conducted by the Japanese military with the operation’s headquarters based in Harbin, Manchuria. Unit 731, also known as the Epidemic Prevention and Water Supply Department, was responsible for the deaths of at least 3000 people in the Manchurian headquarters from 1939-1945 and the experimentation of at least another 250,000. Prisoners were victims of such procedures such as live vivisection, frostbite, and disease experiments, all in the name of furthering Japanese medical, military, and biological warfare research.
Historians estimate that at least half a million people were killed as a direct or indirect result of the biological warfare field tests throughout China, which included airplanes dropping ceramic bombs filled with plague-infested fleas, anthrax contaminating water supplies, and lacing food with other infectious diseases. This biological warfare research was even considered as a tool to attack the United States: the military plan codenamed Cherry Blossoms at Night was in the works, which would have involved kamikaze pilots infesting California with the plague.
Unit 731 was just one of many Epidemic Prevention Departments, with at least 5 other permanent facilities in China, Japan, and Singapore, and at least 18 others throughout the Japanese Empire. However, In August 1945, Japan surrendered to the Allies and Unit 731’s leader, General Shiro Ishii, ordered his more than 10,000 workers to bury the evidence by destroying the facilities, killing and burying the remaining prisoners, releasing all disease-infected animals, and taking their secrets to the grave.
The United States granted General Ishii and a number of other prominent Unit 731 workers immunity from war crime investigations in exchange for the medical research they accumulated from their experiments. The Soviet-U.S. rivalry was soon to turn into the Cold War, and the U.S. wanted to get ahead of the USSR in biological warfare research. The U.S. did not want the publicity of an international war crime trial, which would leak any of the secret and valuable research to the Soviets that the Japanese had accumulated at the high cost of hundreds of thousands of human lives. As a result of this war crime immunity, a number of Unit 731 officials were able to become prominent members of society, including professors at medical schools, the director of Japan’s largest pharmaceutical company, the president of Japan’s Medical Association, and the head of the Japanese Olympic Committee.
Former members of Unit 731, including medical assistants, nurses, and doctors, have come forward and admitted to following the orders to perform experiments on prisoners and to cover up the evidence at the end of the war. However, to this day, the Japanese government has not taken responsibility for the nearly 1 million deaths that Unit 731 and its biological warfare division is estimated to have caused. Neither have any lawsuits filed by Chinese families affected by Unit 731’s research been answered by the Japanese government.
731: Two Versions of Hell. Film produced by James T. Hong. 2007.
“Japan Unearths Site Linked to Human Experiments.” The Guardian. 21 February, 2011.
“Japanese Veteran Admits Vivisection Tests on PoWs.” The Guardian. 27 November, 2006.
“The Imperial Japanese Medical Atrocities and its Enduring Legacy in Japanese Research
Ethics.” Abridged from chapter “The Imperial Japanese Experiments in China” in Oxford
Textbook of Clinical Research Ethics, 2008.
“Unmasking Horror -- A Special Report.; Japan Confronting Gruesome War Atrocity.” The New
York Times 17 Mar. 1995.
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