The Metropolitan Archdiocese of Tokyo is a Latin Church metropolitan archdiocese of the Catholic Church in Japan. It was erected as the Apostolic Vicariate of Japan on May 1, 1846, by Pope Gregory XVI, and its name was later changed by Pope Pius IX to the Apostolic Vicariate of Northern Japan on May 22, 1876.

The Diocese of Niigata is a Latin Church diocese of the Catholic Church located in the city of Niigata in the ecclesiastical province of Tokyo in Japan.