In the 2nd millennium BC, Austronesian people arrived, bringing with them domesticated pigs, chickens, dogs, and obsidian tools.

[4] British and American whaling ships visited the island for provisions, water, and wood in the 19th century.

[12] The referendum question was a choice between greater autonomy within Papua New Guinea or full independence.

Bougainville and the nearby island of Buka are a single landmass separated by a deep 300-metre (980 ft) wide strait.

The island has an area of 9,000 km2 (3,500 sq mi), and there are several active, dormant or inactive volcanoes that can rise to 2,400 m (7,900 ft).

Bagana (1,750 metres [5,740 ft]) in the north central part of Bougainville is conspicuously active, spewing out gas that is visible for many kilometres.

[16] More recently, deforestation in order to feed the growing population has affected the flow of many rivers on the island.

[17][better source needed] The United Nations Environment Programme has offered to facilitate the cleanup of the Panguna mine and explore reopening it with more stringent environmental standards.

The Panguna mine is estimated to have one billion tonnes of copper ore and 12 million ounces of gold.

The larger languages, such as Nasioi, Korokoro Motuna, Terei, and Halia, are split into dialects that are not always mutually understandable.

[24] Other Austronesian languages include Nehan, Petats, Solos, Saposa (Taiof), Hahon and Tinputz, all spoken in the northern quarter of Bougainville, Buka and surrounding islands.

Bannoni and Torau are Austronesian languages not closely related to the former, which are spoken in the coastal areas of central and south Bougainville.

[citation needed] Cut off from the outside world for several years by a Papua New Guinean blockade during the civil war, the islanders suffered many deaths from a lack of medical resources.

[27] The Coconut Revolution, a documentary about the struggle of the indigenous population to save their island from environmental destruction and gain independence, was made in 1999.

[28] An Evergreen Island (2000), a film by Australian documentary filmmakers Amanda King and Fabio Cavadini of Frontyard Films, showed the ingenuity with which the Bougainvillean people survived for almost a decade (1989–1997) without trade or contact with the outside world because of the PNG military blockade.