Imai Fukuzan’s Introduction to Shonan-katto-roku
The origin of warrior Zen in Kamakura, and in the whole of the eastern part of Japan, goes back to the training of warrior pupils by Eisai (Senko Kokushi). But it was the training of warriors and priests by two great Chinese masters, Daikaku and Bukko, which became the Zen style of the Kamakura temples….