Nicholas of Japan was a nineteenth-century Russian Orthodox missionary, theologian, and bishop who played a central role in introducing Eastern Orthodoxy to the Japanese people. Born Ivan Kasatkin in the Smolensk region, he traveled to Japan in 1861 to serve at a consulate chapel. Through his deep study of the Japanese language, culture, and Buddhism, he successfully built a large religious community. He eventually served as the Archbishop of All Japan, leaving a lasting spiritual and linguistic legacy through his extensive translations of sacred texts.