Orthodox Saints site lists him today on his birthday, and has this:
"Born in Russia in 1836, he became one of the great Orthodox missionaries of modern times. As a boy, he resolved to become a missionary in the far East. With the counsel and blessing of Bishop Innocent of Siberia and Alaska, he went to Japan in 1861 and joined a small Russian mission there. Though the mission's official purpose was to minister to the Russian consular community, the consul-general who invited Hieromonk Nikolai hoped to bring the light of the Orthodox Faith to the Japanese people as well.
"Realizing that he could only hope to convert the Japanese people if they understood one another well, Fr Nikolai immersed himself in the study of Japanese thought, culture and language. Over the course of his life he translated most of the Bible and most of the Orthodox services into Japanese, and became a fluent speaker of the language. He encountered much resistance: Preaching of Christian doctrine was officially banned in Japan, and a Samurai once approached him with the words "Foreigners must die!" It was this same Samurai who later became his first Japanese priest. In 1880 he was elevated to Bishop of Japan.
"During the Russo-Japanese war he remained in Japan and labored successfully to overcome nationalist strife that might have harmed or destroyed the Church in Japan. He encouraged all his Japanese faithful to pray for the Japanese armed forces, though he explained that as a Russian he could not do so, and excluded himself from all public services for the duration of the war. He sent Russian-speaking Japanese priests to the prison camps to minister to Russian prisoners of war.
"At the time of his repose in 1912, after forty-eight years in Japan, St Nikolai left a Cathedral, eight churches, more than 400 chapels and meeting houses, 34 priests, 8 deacons, 115 lay catechists, and 34,110 Orthodox faithful. The Church of Japan is now an autonomous Orthodox Church under the care of the Moscow Patriarchate."
This site also has an account of his life: http://oca.org/saints/lives/2016/02/16/100419-st-nicholas-equal-of-the-apostles-and-archbishop-of-japan