The Forgotten 39,000: China’s Forgotten Slave Laborers in Imperial Japan in 1945

by Lily Shores

In the summer of 1945, 986 starving Chinese men at the Hanaoka copper mine in northern Japan snapped. They had been beaten daily, fed less than prisoners of war, and watched their friends die of dysentery and exhaustion. On the night of 30 June, armed with stolen pickaxes and rocks, they killed eight Japanese overseers. More than 200 died in the immediate aftermath from capture and torture by the Japanese military police and local citizens at the Hanaoka town square, and 418 in total perished from malnutrition and abuse by October.[1] The company that ran the mine, Kajima Corporation, is still one of Japan’s largest construction firms with projects such as large-scale infrastructure, urban development, and international projects. In 2025, they are building a flagship venue for the 2025 World Expo.[2] Kajima executives escaped with fines due to U.S. occupation authorities later uncovering mass graves, leading to limited war crimes prosecutions of guards. Seraphim situates this atrocity within the broader political landscape of postwar Japan, where Occupation censorship, Cold War realignment, and domestic repression of the left buried such stories from public memory. The rediscovery of the Hanaoka Monogatari woodblock series in the 1950s, however, transformed local memory into a record of resistance, connecting class oppression, imperialism, and Japan’s moral failure to acknowledge its crimes.[3]

The incident in Hanaoka was not an exception. The forced labor of Chinese civilians under Imperial Japan represents one of the most shocking yet lesser-known atrocities of the Asia-Pacific War. Between 1943 and 1945, nearly 39,000 Chinese men were abducted from occupied North China and transported to Japan to compensate for wartime labor shortages. The system, documented in Japan’s postwar Foreign Ministry Report (FMR), reveals an industrialized network of exploitation and state-corporate complicity that blurred the line between war labor and slavery. 

William Underwood's "Chinese Forced Labor, the Japanese Government and the Prospects for Redress” offers an extensive account of this system’s structure and Japan’s postwar evasion of responsibility.  Beginning in 1945, 39,935 men were brought to 135 worksites across Japan, where over 6,800 died, a death rate of 17.5 percent.[4] Many were abducted during “laborer hunting” raids, tortured, and shipped under inhumane conditions. Once in Japan, they worked long hours in mines and docks, under starvation-level rations, constant beatings, and no pay. The Japanese government’s Foreign Ministry Report, compiled in 1946, detailed these conditions but was later suppressed to prevent reparations claims. Underwood shows how successive administrations deliberately concealed evidence, manipulated data, and blocked citizen groups seeking the reparation of Chinese remains.[5]

Timothy Webster’s "Sisyphus in a Coal Mine” explores how these historical injustices resurfaced through modern legal struggles. Drawing parallels with Holocaust litigation, Webster documents the lawsuits filed by former Chinese slave laborers in Japanese courts beginning in the late 1990s. Despite clear violations of the Hague and Forced Labor Conventions, Japanese courts repeatedly dismissed cases on the grounds of state immunity and expired statutes of limitations.[6] Yet, isolated victories such as the Fukuoka District Court’s 2002 ruling against Mitsui Mining and the Hiroshima High Court’s 2004 decision against Nishimatsu Construction show a gradual acknowledgement of Japan’s wartime labor system as an “outrage against humanity.”[7]  Webster argues for a comprehensive reparations framework, akin to Germany's post-Holocaust settlements, to ensure equitable compensation beyond gradual litigation. 

Japanese textbooks mention “wartime laborers” in a single vague sentence, if at all. The rest of the world had forgotten about the wartime laborers.
And politicians in Tokyo continue to visit Yasukuni Shrine, where the architects of the “man-hunting” policy are honored as gods.
The mass graves at Hanaoka have a small, out-of-the-way memorial that almost no Japanese visitor can find.
Kajima, Mitsui, and Mitsubishi still remain among the world’s largest corporations.

Sources: 
1. Franziska Seraphim, “Hanaoka Monogatari: The Massacre of Chinese Forced Laborers, Summer 1945,” Sciences Po Mass Violence and Resistance – Research Network (2012).
2. CUCO. "Press Release." CUCO: NEDO Green Innovation Fund Project, n.d., www.cuco-2030.jp/english/pressrelease/.
3. Seraphim, “Hanaoka Monogatari.”
4. William Underwood, “Chinese Forced Labor, the Japanese Government and the Prospects for Redress,” The Asia-Pacific Journal: Japan Focus 6, no. 3 (2008): 1–9.
5. Underwood, “Chinese Forced Labor,” 5–7.
6. Timothy Webster, “Sisyphus in a Coal Mine: Responses to Slave Labor in Japan and the United States,” Cornell International Law Journal 46, no. 2 (2013): 517–520.
7. Webster, “Sisyphus in a Coal Mine,” 522–523.