Which religion had the most influence in Japan's military?

SHINTO is predominantly a Japanese religion. According to the Nihon Shukyo Jiten (Encyclopedia of Japanese Religions), “The formation of Shintoism is almost identical with the Japanese ethnic culture, and it is a religious culture that was never practiced apart from this ethnic society.”

The emperor was worshiped as god by his subjects. He was viewed as supreme politically and religiously by reason of his descent from the sun-goddess.
As a result, the teaching was developed that “the center of this phenomenal world is the Mikado’s [Emperor’s] land. From this center we must expand this Great Spirit throughout the world. . . . The expansion of Great Japan throughout the world and the elevation of the entire world into the land of the Gods is the urgent business of the present and, again, it is our eternal and unchanging object.” (The Political Philosophy of Modern Shinto, by D. C. Holtom) There was no separation of Church and State there!

By 1941 the whole nation was mobilized into the war effort of World War II under the banner of State Shinto and in dedication to the “living man-god.” ‘Japan is a divine nation,’ the people thought, ‘and the kamikaze, the divine wind, will blow when there is a crisis.’ Soldiers and their families petitioned their guardian gods for success in the war.

For more detailed information on this subject and others like it, go to jw.org (Online Library) .
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