Pacific Ocean theater of World War II

Japanese naval aircraft prepare to take off from an aircraft carrier.
The Western Allies' command structure in the Pacific
U.S. 5th Marines evacuate injured personnel during actions on Guadalcanal on November 1, 1942.
An SBD Dauntless flies patrol over USS Washington and USS Lexington during the Gilbert and Marshall Islands campaign, November 12, 1943.

The Pacific Ocean theater, during World War II, was a major theater of the war between the Allies and the Axis.[citation needed]

Most Japanese forces in the theater were part of the Combined Fleet (連合艦隊, Rengō Kantai) of the Imperial Japanese Navy (IJN), which was responsible for all Japanese warships, naval aircraft, and marine infantry units. The Rengō Kantai was led by Admiral Isoroku Yamamoto, until he was killed in an attack by U.S. fighter planes in April 1943.[1] Yamamoto was succeeded by Admiral Mineichi Koga (1943–44)[1] and Admiral Soemu Toyoda (1944–45).[2] The General Staff (参謀本部, Sanbō Honbu) of the Imperial Japanese Army (IJA) was responsible for Imperial Japanese Army ground and air units in Southeast Asia and the South Pacific. The IJN and IJA did not formally use joint/combined staff at the operational level, and their command structures/geographical areas of operations overlapped with each other and those of the Allies.

In the Pacific Ocean theater, Japanese forces fought primarily against the United States Navy, the U.S. Marine Corps and the U.S. Army. The United Kingdom, New Zealand, Australia, Canada and other Allied nations also contributed forces.


  1. ^ a b Potter & Nimitz (1960) p.717
  2. ^ Potter & Nimitz (1960) pp.759–760