Koiari Raid

The Koiari Raid was a battle that occurred between 28–29 November 1943 in the Pacific theater of World War II between American and Japanese forces. Part of the Bougainville campaign, the raid involved a landing by a battalion-sized force of United States Marines to harass Imperial Japanese Army troops on Bougainville Island. The raid was a failure for the Americans as they were attacked by a larger-than-expected Japanese force and as a result the Marines were withdrawn from the beachhead without having achieved any of their objectives.

Background

The US commander, General Roy Geiger, wanting to increase the beachhead perimeter that had been established around Torokina to include a ridge of hills 2,000 yards (1,800 m) away, ordered an eastward advance towards the Torokina River, aimed at establishing an inland defense line codenamed "Fox". The advance was to proceed on 26 November. In order to protect the general advance from any surprise Japanese attack on the right flank, Geiger planned a raid at Koiari, 10 miles (16 km) down the coast from Cape Torokina, to detect enemy troop movements, destroy enemy supply dumps and disrupt their line of communications. The raiders were to harass enemy units as far inland as the East–West trail but avoid any decisive engagement with major Japanese forces.