Unit 731 - Formation

Formation

In 1932, General Shirō Ishii (石井四郎 Ishii Shirō), chief medical officer of the Japanese Army and protégé of Army Minister Sadao Araki was placed in command of the Army Epidemic Prevention Research Laboratory. Ishii organized a secret research group, the "Tōgō Unit", for the conduct of various chemical and biological investigations in Manchuria. Ishii had proposed the creation of a Japanese biological and chemical research in 1930, after a two-year study trip abroad, on the grounds that Western powers were developing their own programs. One of Ishii´s main supporters inside the army was Colonel Chikahiko Koizumi, who later became Japan's Health Minister from 1941 to 1945. Koizumi had joined a secret poison gas research committee back in 1915, during World War I, when he and other Japanese army officers were impressed by the successful German use of chlorine gas at the second battle of Ypres, where the Allies suffered 15,000 casualties as result of the chemical attack.

Unit Tōgō was implemented in the Zhongma Fortress, a prison/experimentation camp in Beiyinhe, a village 100 km (62 mi) south of Harbin on the South Manchurian Railway. A jailbreak in autumn 1934 and later explosion (believed to be an attack) in 1935 led Ishii to shut down Zhongma Fortress. He received the authorization to move to Pingfang, approximately 24 km (15 mi) south of Harbin, to set up a new and much larger facility.

In 1936, Hirohito authorized, by imperial decree, the expansion of this unit and its integration into the Kwantung Army as the Epidemic Prevention Department. It was divided at the same time into the "Ishii Unit" and "Wakamatsu Unit" with a base in Hsinking. From August 1940, all these units were known collectively as the "Epidemic Prevention and Water Purification Department of the Kwantung Army (関東軍防疫給水部本部)" or "Unit 731" (満州第731部隊) for short.