Buka Island is the second largest island in the Papua New Guinea

Papua New Guinea

Papua New Guinea , officially the Independent State of Papua New Guinea, is a country in Oceania, occupying the eastern half of the island of New Guinea and numerous offshore islands...

n province of Bougainville

Bougainville Province

The Autonomous Region of Bougainville, previously known as North Solomons, is an autonomous region in Papua New Guinea. The largest island is Bougainville Island , and the province also includes the island of Buka and assorted outlying islands including the Carterets...

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Buka was first occupied by humans in paleolithic times, some 30,000 years ago. The present inhabitants speak languages that in all likelihood stem from the eastward push of Austronesian languages of the so-called Lapita

Lapita

Lapita is a term applied to an ancient Pacific Ocean archaeological culture which is believed by many archaeologists to be the common ancestor of several cultures in Polynesia, Micronesia, and some coastal areas of Melanesia...

 Culture complex, some 2,700 years ago.
The island was occupied by Japan during World War II.