"Kagemusha" (the body double) is a person, during the Sengoku period (the period of warring states), employed by a busho (a Japanese military commander) as his straw man dressed in the identical clothes as his.
影武者（かげむしゃ）とは、日本の戦国時代(日本)の武将などが用いた、自分と同じ服装をさせて身代わりとさせた人物のこと。