Sasebo Naval District

Sasebo Naval District was the third of five main administrative districts of the pre-war Imperial Japanese Navy. Its territory included the western and southern coastline of Kyūshū, the Ryukyu Islands, Taiwan and Korea, as well as patrols in the East China Sea and the Pacific
Sasebo also contained the Sasebo Naval Arsenal, specializing mostly in destroyers and smaller warships; and its anchorage was one of the largest in Japan. The District encompassed anchorages at Imari and Hirado ports as well as the designated third echelon naval ports yokobu of Takeshiki, Kagoshima, Kuji, and Wakamatsu

History

The location of Sasebo facing China and Korea, and near the foreign treaty port of Nagasaki was recognized of strategic importance by the leaders of the early Meiji government and early Imperial Japanese Navy. In 1883, the then Lieutenant Commander Tōgō Heihachirō nominated what was a tiny fishing village as the ideal location for a naval base. With the formation of the navy in 1886, Japan was divided into five Naval Districts each with a headquarters. Sasebo was designated as the "Third Naval District", and its harbor was dredged, a breakwater constructed and docking, coaling and repair facilities for warships were established, and the military base was officially opened in 1889. To stress the importance of the base, Emperor Meiji made a personal inspection tour in 1890.
The base was connected to the rest of Japan by rail in 1898, and the Sasebo Naval Arsenal, which would eventually expand to become one of the largest shipyards in Japan for the construction of smaller warships, began operation in 1903. As with the other Naval Districts, Sasebo was intended to operate as independently as possible, and facilities included armories, production factories for torpedoes, naval mines and naval artillery, and also a naval hospital and training centers. In concept, the Naval District was similar to the United States Navy Sea Frontiers concept. the Naval District maintained a small garrison force of ships and Naval Land Forces which reported directly to the Guard District commander, and hosted detachments of the numbered fleets on a temporary assignment basis.
Sasebo was the closest ship repair facility for the Imperial Japanese Navy to the combat zones of the Russo-Japanese War and saw considerable activity during that conflict.
In 1920, the Japanese navy established an air wing and a wireless communications center in 1922. In 1934, the Tomozuru capsized off Sasebo with loss of most of its crew, and leaving behind serious questions about the basic design of many Japanese warships.
In 1941, base facilities were expanded considerably for the Pacific War. The base also hosted a major portion of the Japanese Special Naval Landing Forces. The Imperial Japanese Navy had some 60,000 people working in the dock yard and associated naval stations at the peak of World War II, outfitting ships, submarines and aircraft.
Most of the base was destroyed by American air raids on Japan on June 28, 1945. After the surrender of Japan, Sasebo was occupied by the U.S. Marine Corps' Fifth Division, and the Sasebo Naval District was formally abolished on November 30, 1945.
Part of the former base facilities is still in use by the United States Navy as the United States Fleet Activities Sasebo and by the Japan Maritime Self-Defense Force. One of the former base structures is now a museum.

Order of Battle at time of the attack on Pearl Harbor

Third Naval District
*AO Sata
*Sasebo Naval Base
**Base HQ
**Communications
**Supply
**Accounting
**Construction
**Ports & Docks
**Navy Yard
**Navy Hospital
**Navy Prison
**Naval Fuel Depot
**Base Garrison
**Special Naval Landing Forces
*Sasebo Submarine Base
*Sasebo Air Group
**16x Mitsubishi A5M Claude
**6 x Aichi E13A Jake
**15 x Kawanishi H6K Mavis
*Sasebo Guard Force
**Sasebo Coastal Defense Squadron
***PM Kozan Maru
** Sasebo Local Defense Squadron
***PG Sinkyo Maru
*** PG Sinkyo Maru #5
** Minesweeper Division 42
*** AMc Seki Maru
*** AMc Toshi Maru #7
*Oshima Guard Force
**AMc Chuon Maru #8
**AMc Hakata Maru #7
**AMc Himejima Maru
**Minesweeper Division 41
***AMc Kyo Maru #1
***AMc Kyo Maru #3
***AMc ''Kyo Maru #5''

List of commanders

Chief of Staff

Captain Tameo Nakamizo
Rear-Admiral Koreyoshi Ogata
Rear-Admiral Masanaga Matsumura
Rear-Admiral Tadashi Nomura
Vice-Admiral Nagataka Uemura
Vice-Admiral Tomomichi Onomoto
Vice-Admiral Yoshitomo Inoue
Captain Masaki Hashimoto
Rear-Admiral Ichiro Nijima
Rear-Admiral Tasuku Serata
Admiral Motaro Yoshimatsu
Vice-Admiral Hikohachi Yamada
Rear-Admiral Shinjiro Uehara
Vice-Admiral Baron Toshiatsu Sakamoto
Admiral Motaro Yoshimatsu
Rear-Admiral Ichiro Nijima
Vice-Admiral Koshi Saito
Rear-Admiral Genzaburo Ogi
Vice-Admiral Baron Shinrokuro Nishi
Vice-Admiral Tamotsu Tsuchiya
Admiral Baron Gentaro Yamashita
Rear-Admiral Genzaburo Ogi
Vice-Admiral Yasutaro Egashira
Admiral Kaneo Nomaguchi
Vice-Admiral Rinroku Eguchi
Vice-Admiral Otojiro Ito
Rear-Admiral Ichitaro Nakajima
Vice-Admiral Tomojiro Chisaka
Vice-Admiral Hiromi Tadakoro
Vice-Admiral Hanroku Saito
Vice-Admiral Nobutaro Shimomura
Admiral Saburo Hyakutake
Vice-Admiral Kenzo Kobayashi
Rear-Admiral Kametaro Muta
Vice-Admiral Shiro Furukawa
Vice-Admiral Yukichi Shima
Vice-Admiral Togo Kawano
Vice-Admiral Akira Fujiyoshi
Vice-Admiral Giichiro Kawamura
Vice-Admiral Yoshiyuki Niiyama
Vice-Admiral Eikichi Katagiri
Rear-Admiral Hiroyoshi Tabata
Vice-Admiral Ibō Takahashi
Vice-Admiral Mitsumi Shimizu
Vice-Admiral Hidesaburo Koori
Vice-Admiral Masami Kobayashi
Vice-Admiral Kakuji Kakuta
Vice-Admiral Shigenori Horiuchi
Vice-Admiral Gisaburo Yamaguchi
Vice-Admiral Masaki Ogata
Vice-Admiral Shigeji Kaneko
Rear-Admiral Keishi Ishii