After the Sino-Japanese War, the Russo-Japanese War, and two world wars, foreign people took growing interests in Japanese strategies and tactics, a moral sense, and what was behind loyalty and patriotism, so a Japan study was pursued such as "The Chrysanthemum and the Sword" by Ruth Benedict and "Zen in the Art of Archery" by Eugen Herrigel.
日清戦争・日露戦争、そして二度の世界大戦を経て、海外で日本人の戦略や戦術、道義心、忠君愛国の背景にあるものへの関心が深まると、ルース・ベネディクトの『菊と刀』やオイゲン・ヘリゲルの『弓と禅』といった日本研究が進んだ。