In a land area of 2,276 square kilometers, the diocesan territory covers Kagoshima prefecture.
In the diocesan territory, the population is 1,432,871 at end of 2016. Most of them are ethnic Japanese. There are also 9,126 non-Japanese people, according to the Immigration Bureau of Japan.
The territory also has many languages/dialects.
On March 18, 1927, Okinawa prefecture and Kagoshima Prefecture were separated from the Nagasaki diocese and became the prefecture apostolic of Kagoshima. In accord with the San Francisco Peace Treaty at the end of the Second World War, Okinawa prefecture and the Southern Islands of Kagoshima prefecture came under American military occupation. For this reason, Okinawa and the Southern Islands were separated from the prefecture apostolic of Kagoshima and came directly under the Holy See. They were entrusted to the American Capuchin Friars (New York Province) and became the administration apostolic of the Ryukyus. On Jan. 21, 1949, Father Felix Ley, O.F.M. Cap. was appointed administrator apostolic.
On May 8, 1955, Amamioshima and others of the Southern Islands were returned to Japan and became part of the diocese of Kagoshima.
On June 9, 1968, Monsignor Ley was consecrated bishop and became a member of the bishops' conference until his sudden death on Jan. 23, 1972.
In May 1972, Japan resumed sovereignty over Okinawa and on Dec. 18 that year the administration apostolic of Ryukyus was raised to the status of a diocese, becoming the diocese of Naha. On Feb. 11, 1973, Father Tadamaro Ishigami, O.F.M.Cap., was consecrated and became the first bishop of Naha.
On March 20, 1997, Pope John Paul II accepted the resignation of Bishop Ishigami, and appointed Father Toshio Oshikawa, to succeed him. He was consecrated bishop of Naha on May 25, 1997.
Airplanes, railways, buses and ships are in use in the diocesan territory.
Throughout Japan, literacy is 99 percent, according to the Central Intelligence Agency, US, report 2010.