[1] On 29 November 1941, Operation Gi [2] (for Gilbert Islands) was decided within the Japanese 4th Fleet and departed from Truk, headquarters of the South Seas Mandate.

The Japanese occupation of the Northern Gilbert Islands can be divided into three periods: On the day of their attack on Pearl Harbor, Japanese military forces embarked on board the minelayer Okinoshima which was serving as flagship for Admiral Kiyohide Shima in Operation Gi (the invasion of the Gilbert Islands) and had deployed from Jaluit with a Special Naval Landing Force (SNLF).

A few hours before the Makin occupation, on 10 December 1941, the same Japanese landing military (DesDiv 29/Section 1's Asanagi and Yūnagi) also visited Tarawa, where they rounded up the Europeans and informed them that they could not leave the atoll without the permission of the naval commander, Kiyohide Shima.

On September, some remote central and southern islands were also briefly visited or occupied (Tamana was the southernmost) especially in order to destroy the Coastwatchers network, headquartered on Beru.

[6] On 15 September 1942, Japanese forces occupied Tarawa and began fortifying the atoll, mainly Betio islet where they built Hawkins Field, an airfield.

[7] The first offensive operation from the new American airfield at Funafuti was launched on 20 April 1943 when 22 B-24 Liberator aircraft from 371 and 372 Bombardment Squadrons bombed Nauru.

[8] On 6 November 1943, the United States Seventh Air Force established its forward headquarters base on Funafuti, to prepare the battle of Tarawa.

In February 1942, the Free French destroyer Le Triomphant evacuated the remaining Europeans and Chinese from Ocean Island.

Before the end of the year, the 280 Banabans who survived the war on Nauru, Tarawa, Kosrae or Truk were resettled on Rabi Island in Fiji.