In a land area of 28,418 square kilometers, the diocesan territory covers Aichi, Gifu, Ishikawa, Fukui and Toyama prefectures.
In the diocesan territory, the population is 12,505,688 at end of 2016. Most residents are ethnic Japanese. There are also 293,095 non-Japanese people, according to the Immigration Bureau of Japan.
The territory also has many languages/dialects.
The prefecture apostolic of Nagoya was established on Feb. 19, 1922, when the two prefectures of Aichi and Gifu were separated from the archdiocese of Tokyo and the three prefectures of Fukui, Ishikawa, and Toyama were separated from the prefecture apostolic of Niigata. The new prefecture apostolic was entrusted to the German Fathers of the Society of the Divine Word, and Monsignor Joseph Reiners, S.V.D., who was also prefect apostolic of Niigata, was appointed concomitantly prefect apostolic of Nagoya. In 1926 Monsignor Reiners resigned and became prefect apostolic of Nagoya alone. In 1941, Father Magoshiro Matsuoka took over responsibility for both Niigata and Nagoya as administrator apostolic. In 1945 Monsignor Matsuoka became prefect apostolic of both Niigata and Nagoya. In 1953 he resigned. On April 16, 1962, the prefecture apostolic of Nagoya was raised to the status of a diocese, and Monsignor Matsuoka was consecrated as the first bishop. In 1969 Bishop Matsuoka resigned, and in the same year Father Nobuo Soma was consecrated bishop.
On April 5, 1993, Bishop Soma resigned and Father Jun'ichi Nomura was appointed his successor. He was consecrated on July 4 of the same year.
On March 29, 2015, Bishop Nomura resigned, and auxiliary bishop of Osaka, Goro Matsuura, was appointed bishop of Nagoya. He was installed on June 13.
Airplanes, railways, ships and buses are in use in the diocesan territory.
Throughout Japan, literacy is 99 percent, according to the Central Intelligence Agency, US, report 2010.