linguistic:paraphrasing, structural:reformatting
Prehistory

The Solomons were first settled by people coming from the Bismarck Islands and New Guinea during the Pleistocene era c. 30,000–28,000 BC, based on archaeological evidence found at Kilu Cave on Buka Island in the Autonomous Region of Bougainville, Papua New Guinea. At this point sea levels were lower and Buka and Bougainville were physically joined to the southern Solomons in one landmass ("Greater Bougainville"), though it is unclear precisely how far south these early settlers spread as no other archaeological sites from this period have been found. As sea levels rose as the Ice Age ended c. 4000–3500 BC, the Greater Bougainville landmass split into the numerous islands that exist today. Evidence of later human settlements dating to c. 4500–2500 BC have been found at Poha Cave and Vatuluma Posovi Cave on Guadalcanal. The ethnic identity of these early peoples is unclear, though it is thought that the speakers of the Central Solomon languages (a self-contained language family unrelated to other languages spoken in the Solomons) likely represent the descendants of these earlier settlers.

From c. 1200–800 BC Austronesian Lapita people began arriving from the Bismarcks with their characteristic ceramics. Evidence for their presence has been found across the Solomon archipelago, as well at the Santa Cruz Islands in the south-east, with different islands being settled at different times. Linguistic and genetic evidence suggests that the Lapita people "leap-frogged" the already inhabited main Solomon Islands and settled first on the Santa Cruz group, with later back-migrations bringing their culture to the main group. These peoples mixed with the native Solomon Islanders and over time their languages became dominant, with most of the 60–70 languages spoken there belonging to the Oceanic branch of the Austronesian language family. Then, as now, communities tended to exist in small villages practising subsistence agriculture, though extensive inter-island trade networks existed. Numerous ancient burial sites and other evidence of permanent settlements have been found from the period AD 1000–1500 throughout the islands, one of the most prominent examples being the Roviana cultural complex centred on the islands off the southern coast of New Georgia, where a large number of megalithic shrines and other structures were constructed in the 13th century. The people of Solomon Islands were notorious for headhunting and cannibalism before the arrival of the Europeans.