Japanese war crimes occurred in many Asian countries during the period of Japanese imperialism, primarily during the Second Sino-Japanese War and World War II. Some of the incidents have also been described as an Asian Holocaust and Japanese war atrocities. Some war crimes were committed by military personnel from the Empire of Japan in the late 19th century, although most took place during the first part of the Shōwa Era, the name given to the reign of Emperor Hirohito, until the military defeat of the Empire of Japan, in 1945.
Historians and governments of some countries hold Japanese military forces, namely the Imperial Japanese Army, the Imperial Japanese Navy and the Imperial Japanese family, especially Emperor Hirohito, responsible for killings and other crimes committed against millions of civilians and prisoners of war. Some Japanese soldiers have admitted to committing these crimes.
Since the 1950s, senior Japanese Government officials have issued numerous apologies for the country’s war crimes. Japan’s Ministry of Foreign Affairs states that the country acknowledges its role in causing “tremendous damage and suffering” during World War II, especially in regard to the IJA entrance into Nanjing during which Japanese soldiers killed a large number of noncombatants and engaged in looting and rape. However, some members of the Liberal Democratic Party in the Japanese government such as former prime minister Junichiro Koizumi and current Prime Minister Shinzo Abe have prayed at the Yasukuni Shrine, which includes convicted Class A war criminals in its honored war dead. Some Japanese history textbooks only offer brief references to the various war crimes, and members of the Liberal Democratic Party such as Shinzo Abe have denied some of the atrocities such as the use of comfort women. In addition to Japanese military and civil personnel, Allied authorities found that Korean and Taiwanese serving in the forces of the Empire of Japan also committed war crimes.
R. J. Rummel, a professor of political science at the University of Hawaii, estimates that between 1937 and 1945, the Japanese military murdered from nearly 3,000,000 to over 10,000,000 people, most likely 6,000,000 Chinese, Indonesians, Koreans, Filipinos and Indochinese, among others, including Western prisoners of war. According to Rummel, “This democide [i.e., death by government] was due to a morally bankrupt political and military strategy, military expediency and custom, and national culture.” According to Rummel, in China alone, during 1937–45, approximately 3.9 million Chinese were killed, mostly civilians, as a direct result of the Japanese operations and 10.2 million in the course of the war. The most infamous incident during this period was the Nanking Massacre of 1937–38, when, according to the findings of the International Military Tribunal for the Far East, the Japanese Army massacred as many as 300,000 civilians and prisoners of war, although the accepted figure is somewhere in the hundreds of thousands.
In Southeast Asia, the Manila massacre of February 1945 resulted in the death of 100,000 civilians in the Philippines. It is estimated that at least one out of every 20 Filipinos died at the hand of the Japanese during the occupation. In the Sook Ching massacre of February 1942, Lee Kuan Yew, the ex-Prime Minister of Singapore, said during an interview with National Geographic that there were between 50,000 and 90,000 casualties. There were other massacres of civilians, e.g. the Kalagong massacre. In wartime Southeast Asia, the Overseas Chinese and European diaspora were special targets of Japanese abuse; in the former case, motivated by an inferiority complex vis-à-vis the historic expanse and influence of Chinese culture that did not exist with the Southeast Asian indigenes, and the latter, motivated by a racist Pan-Asianism and desire to show former colonial subjects the impotence of their Western masters.
Historian Mitsuyoshi Himeta reports that a “Three Alls Policy” (Sankō Sakusen) was implemented in China from 1942 to 1945 and was in itself responsible for the deaths of “more than 2.7 million” Chinese civilians. This scorched earth strategy, sanctioned by Hirohito himself, directed Japanese forces to “Kill All, Burn All, and Loot All.” Additionally, captured allied service personnel were massacred in various incidents, including:
- Laha massacre
- Banka Island massacre
- Parit Sulong
- Palawan Massacre
- SS Tjisalak massacre perpetrated by Japanese submarine I-8
- Wake Island massacre – see Battle of Wake Island
- Bataan Death March
- Shinyo Maru Incident