In the fall of 1937, the Empire of Japan began recruiting Taiwanese into its military; prior to that, Taiwanese were banned from serving in the military of Imperial Japan. As the war continued, there was an increasing need of translators for conducting military operations in China, and many Taiwanese volunteers were given training courses in Min, Cantonese and Mandarin languages, and served as translators for the Imperial Japanese Army operating in China. The number of Taiwanese serving in this capacity was classified, and remains unknown.