The occupation of Majuro (31 January 1944) was the first American invasion of pre-war Japanese territory, but was almost entirely unopposed (Operation Flintlock).
Majuro Atoll was at the eastern end of the Marshalls, and had been added to the target list for Operation Flintlock at the request of Admiral Spruance, who wanted a secure base nearer to existing US bases in the Gilberts.
Majuro was to be attacked by the Majuro Attack Group (Task Group 51.2) under Admiral Hill (The attack group contained one heavy cruiser (Portland), two escort carriers (Nassau and Natoma Bay), four destroyers (Bullard, Black, Kidd and Chauncey), one mine sweeper, one attack transport, one troop transport (Kane) and two high speed transports), and the Majuro Landing Force, made up of the 2nd Battalion, 106th Infantry (28th Infantry Regiment) and the V Amphibious Corps Reconnaissance Company under Lt. Col Frederick B. Sheldon, a total of 1,500 troops. Events would soon prove that this was a rather impressive level of overkill.. Admiral Hill commanded the invasion from the APA Cambria, partly converted to a HQ ship.
Majuro Atoll was long and narrow, running from west to east. The main route into the atoll was the Calalin Pass, which had tiny Eroj Island to the west and the larger Catalin Island to the east. Three more named islands - Darrit, Uligo and Dalap made up the eastern end of the atoll. The largest island by far was Majuro Island, which stretched out along most of the southern side of the atoll.
At 0500 on 30 January the Kane left the main group and made directly for Majuro. At 2130 on 30 January the part of the reconnaissance troop landed on Calalin Island. The first native they found told them that there were 300-400 Japanese on Darrit Island, but none anywhere else. The Kane dropped off the rest of the reconnaissance group on Dalap Island. They found a native who told them that there were only four Japanese on the atoll, all on Majuro Island. They then found Michael Madison, who was half English, and confirmed this second report.
At 0600 on 31 January the bombardment of Darrit Island began. The party on Dalap managed to get in touch with the fleet and cancel the bombardment. They then investigated the island and confirmed that it was unoccupied.
At 2145 forty two Marines from the reconnaissance force landed on Majuro Island. They advanced along the island, and found that it was indeed almost unoccupied. The only Japanese on the island was Warrant Officer Nagata of the IJN, who had been left behind as a caretaker. Majuro Atoll was thus occupied without a fight, and quickly became an important American base.