During the Second World War, Japan took about 140,000 prisoners of war (POWs) from Western Allied countries (also known in the UK as Far East prisoners of war, FEPOW), as well as tens of thousands of Indian and Filipino POWs and several hundred thousands of Chinese POWs. These POWs suffered extreme mistreatment in Japanese captivity, characterized by forced labor, severe malnutrition, disease, physical abuse, and mass executions. The Imperial Japanese Army disregarded international conventions on the humane treatment of POWs, subjecting captives to brutal conditions in prison camps, on forced marches, and aboard transport ships known as "hell ships". Many POWs were forced into labor on large-scale infrastructure projects, including the infamous Burma-Siam Railway, where tens of thousands perished. Japanese forces also conducted biological and chemical experiments on prisoners, most notably through the activities of Unit 731.
Japan had previously ratified the Hague Conventions of 1899 and 1907, which outlined the rights of prisoners of war, but did not ratify the Geneva Convention. The Japanese military's treatment of POWs in World War II was significantly harsher than its treatment of prisoners during the Russo-Japanese War and World War I, reflecting the country's growing militarization, nationalist ideology, and rejection of Western norms. While the Allies generally adhered to the Geneva Convention in their treatment of Japanese POWs, Japan, like other Axis powers and the USSR, did not reciprocate, instead embracing a military culture that viewed surrender as dishonorable and POWs as unworthy of protection.
The death rate for Western Allied POWs in Japanese custody was significantly higher than that in German or Italian hands, reaching nearly 30% for some nationalities. Non-Western POWs, including Chinese, Filipino, and Indian soldiers, often faced even worse conditions, with mass executions of Chinese prisoners being common; the death rate for Chinese POWs has been estimated at least 40% and likely much higher. The mistreatment of POWs became a focal point of post-war war crimes trials, though many of those responsible evaded prosecution. The suffering endured by Allied prisoners left a lasting impact on historical memory, shaping post-war perceptions of Japan's role in World War II. Despite extensive documentation and survivor accounts, the subject remains contentious, with some instances of denial or minimization of related war crimes in Japan.
Background
Japan ratified the Hague Conventions of 1899 and 1907 which contained provisions regarding humane treatment of prisoners of war. Japan did sign the Geneva Convention on Prisoners of War, but did not ratify it.
Japanese treatment of POWs in World War II was significantly less humane than their treatment of Russian prisoners it held during the Russo-Japanese War and German prisoners it held during World War I (when it was a member of the Allies/Entente). This has been explained with the changing mindset of the Japanese during that timeframe; in the early 20th century, Japan was more friendly towards Western culture, and strived to respect Western norms to appear "civilized". By the 1930s Japanese nationalism turned the country much more xenophobic; the Western origin of the laws such as the stipulation of the Geneva Convention made them unpopular (after the war, many Japanese accused of crimes against POWs, including mid-ranking soldiers, claimed they had never even heard of the convention), the interpretation of Bushido became much more harsh, and the concept of surrender became much more dishonorable (the Senjinkun military code drafted in 1940 and instituted the next year specifically forbade retreat or surrender). As a result, Japanese saw those who surrendered to them as unworthy of protection; it also reduced the likelihood of their own troops surrendering.
Additionally, by the time it engaged Allied forces, the Japanese military was already radicalized by its war in China (the Second Sino-Japanese War that begun in 1937) and accustomed to drastic actions (most infamously, the Nanjing Massacre, where Chinese civilians and also prisoners of war were murdered). Beatings were also a common way to enforce discipline in the Japanese Imperial Army, and in POW camps, this meant that prisoners of war received the worst beatings of all, partly in the belief that such punishments were merely the proper technique to deal with disobedience. Historians have also attributed war crimes to the lack of supervision and disorganization within the Japanese military, where lack of effective court martial procedures allowed for war crimes to go unpunished and therefore continue. The phenomenon of gekokujō which involves lower-ranking officers overthrowing or assassinating their superiors, also allowed for the proliferation of war crimes because if commanders tried to restrict atrocities that served to relieve boredom or stress of the troops, they would either face mutiny or reassignment.
In 1942, General Tojo Hideki (Japanese war minister and prime minister) stated that Japan would treat POWs according to its own traditions and customs, effectively distancing Japan from the Western traditions and the Geneva conventions, and specifically encouraging the use of POWs for forced labor (which was forbidden by the Geneva Convention). Forced labor provided a significant boost to the Japanese wartime economy. Additionally, in an attempt to deter bombing raids over Japan, Japanese authorities sanctioned the executions of Allied airmen shot down over Japan.
Conditions
While traditionally, authorities often moderated their treatment of POWs due to fear of retaliation, in the early stages of the war, the number of POWs held by both sides of the Asian and Pacific theater varied drastically: by the end of 1942 Japanese POWs in Allied hands numbered well under a thousand, while there were over 200,000 British Commonwealth and American prisoners in Japanese hands. Further, Japan refused to publicly acknowledge the fact that any of its soldiers were taken prisoner; in 1943 Japanese Foreign Minister Shigemitsu Mamoru said that "our Army maintains the position that Japanese prisoners of war do not exist."
Australian and other allied captives were held in a notorious prison camp, known as Changi, alongside various other work subcamps in the Burma theatre.
Conditions in Japanese POW camps were harsh; prisoners were forced to work, beaten for minor infractions, starved and denied medical treatment. Those who attempted to escape and were captured were executed or tortured (often by Kempeitai, the Japanese military secret police). The brutality of forced labor is exemplified the case of the Burma-Siam railway, where 16,000 out of 40,000 POWs assigned there as the workforce died. Particularly infamous were the atrocities of Unit 731 which tested biological and chemical weapons on POWs as well as conditions aboard Japanese transport ships known as hell ships (thousands of POWs died during transport on such vessels). Thousands of POWs perished in death marches (ex. Sandakan Death Marches or the Bataan Death March).
Nonetheless, according to Sarah Kovner, "much of the suffering of Allied POWs and internees resulted from Japanese logistical failures and inadequate planning for camps, not prior intent". She concludes that in Japan, with regards to Allied prisoners (except the Chinese) "there was no overarching policy or plan to make POWs suffer, or starve them, or work them to death. There was little policy of any kind. POWs were simply not a priority... [most] camps were run by individual officers, and sometimes NCOs, in far-flung locales" and their commanders were given much autonomy; some prisoners experienced very harsh conditions; others were treated reasonably well. Kovner's claims have not been supported by other researchers, and in fact have been disputed by some critics in the field.
It has also been argued that a significant amount of POW fatalities, perhaps more than half, were the result of friendly fire (sinking of Japanese ships transporting Allied POW, and collateral damage from air raids). One estimate suggested that 19,000 of the Allied POW fatalities in the Pacific theatre came from friendly fire accidents. On the other hand, Japanese rescue efforts during such accidents were lackluster; for example, after the sinking of Japanese hell ship Arisan Maru by an American submarine, Japanese ships secured control of the area, but rescued only Japanese seamen, ignoring the nearly 2,000 POWs, most of whom perished at sea. While some have accused the Japanese Army of purposely exposing POWs to air raids, Kovner notes that the fact that many POW camps were located near the high-priority targets was due to Japanese use of POWs as laborers in those areas; the Japanese administration agreed to relocate some camps away from areas of danger from air raids, but only if it did not affect the use of POWs as laborers.
It was only in August 1945, shortly before the end of the war, as the Japanese were preparing for surrender, that the Japanese government issued instructions calling for better POW treatment.
Japanese prisoners of war
Despite Japanese treatment of the Allied prisoners, the Allies respected the international conventions and treated Japanese prisoners in the camps well. However, in some instances, Japanese soldiers were executed after surrendering (see Allied war crimes).
The situation became somewhat reversed at the end of the war, when large numbers of Japanese troops surrendered to the Allies. S. P. MacKenzie noted that "Food shortages, disease, and a certain amount of vindictive callousness among Allied troops" resulted in thousands of deaths among the Japanese POWs; the situation was much worse for the Japanese prisoners of war in the Soviet Union (approximately half of the 600,000 Japanese troops captured by the Soviets remained "unaccounted" decades after the war).
After the war Trials
Japanese accused of war crimes, including atrocities and abuse of prisoners of war, were subject to post-war trials (see International Military Tribunal for the Far East and Yokohama War Crimes Trials for American-led trials; additional trials were held by the British, Australians, Dutch, Chinese and the USSR); most ended by the turn of the decade. Those convicted of crimes against (among others) POWs included high-ranking officers (such as general Tomoyuki Yamashita) to low-ranking prison guards and civilians; most trials were of mid-ranking officers. Many defendants were found guilty and executed or sentenced to life in prison. The trials were criticized for focusing on low or mid-ranking soldiers, as well as non-Japanese (soldiers from the former Japanese colonial empire, such as Koreans and Taiwanese); the latter also faced more discrimination from the Japanese government.