Some history:
Japan introduced Military Note in 1938 for use in the areas of China that they had occupied. The note was created by taking partially completed Japanese homeland notes and overprinting them on the front and back with four large red characters that read "Military Note". In 1940 the Military Notes were replaced by notes issued by the Japanese puppet banks in China, however the Military Yen continued to be used in Hong Kong and Hainan Island throughout the war.
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