Nissan Island (also Green Island) is the largest of the Green Islands of Papua New Guinea. It is located at 4°30′S 154°13′E / 4.500°S 154.217°ECoordinates: 4°30′S 154°13′E / 4.500°S 154.217°E, about 200 km east of Rabaul on New Britain and about 200 km north-west of Bougainville.
During World War II, in the Battle of the Green Islands, US and New Zealand troops recaptured several islands from heavily outnumbered Imperial Japanese forces. The New Zealand 3rd Division landed on Nissan Island on 15 February 1944 as part of the Solomon Islands campaign to isolate the Japanese stronghold at Rabaul. Shortly after the landings two airfields were constructed on the island.Richard Nixon was a supply officer on the base, and is remembered as being popular with the indigenous inhabitants. There was also a PT boat base on another island nearby. There were approximately 17,000 allied troops on the island at that time. Much of the indigenous population was removed to Guadacanal for about 7–9 months. After that time the front line had moved closer to Japan and the island was no longer needed in the war effort.