Kanō Jigorō
When Kanō Jigorō began to develop judo from jujutsu, his efforts met with opposition from jujutsu practitioners. However, Kano drew a loyal following that included exceptional fighters. Hence the term "Four Guardians of the Kōdōkan" came into existence referring to Tsunejiro Tomita along with Yamashita Yoshitsugu, Yokoyama Sakujiro, and Saigō Shirō.