Excerpts from Books and Wikipedia
"He brought back a more rigorous form of Buddhism known in Japan as Zen. . . . He was the first Japanese monk to be recognized as a Zen master, and he strengthened relationships between monasteries in Japan and China. . . . By also teaching the Rinzai should include defending the state and taking part in public ceremonies, Eisai attracted many samurai, who used his teachings to inform the practice of the martial arts. One of his disciples, Dogen, who also studied in China, returned to Japan in 1227 to set up an alternative Soto school of Zen, which emphasized sitting in meditation as the means for achieving and expressing enlightenment. The Soto school acquired a more popular following, and is now the main school of Zen in Japan." [Furtado: 1001 Days]