Bantu

The Bantu languages form a subgroup of the Niger-Congo family comprising approximately 500 languages spoken by around 350 million people across the southern two-thirds of Africa. The term "Bantu" refers to the shared word for "people" (variants of *bantʊ) across the family, coined by Wilhelm Bleek in 1862. It is one of the most intensively studied language groups in historical linguistics because its expansion is both linguistically traceable and, unusually, genetically and archaeologically documented in high resolution.

Proto-Bantu is reconstructed as having been spoken in or near the Nigeria-Cameroon border region, in what linguists call the Benue-Congo heartland, around 3000–2500 BCE. The earliest Bantu speakers were farmers growing yams and oil palms in the West African rainforest belt. As they moved southward and eastward, the expansion bifurcated: a western stream moved down the Atlantic coast toward the Congo Basin, while an eastern stream skirted the north of the equatorial rainforest and entered East Africa, where Bantu farmers encountered existing populations of Cushitic pastoralists and Khoisan hunter-gatherers.

Ancient DNA from sites across sub-Saharan Africa has transformed understanding of this expansion. Studies of ancient remains from the Congo Basin, East Africa, and southern Africa consistently show that pre-Bantu hunter-gatherer populations (related to the western Rainforest Hunter-Gatherers and the southern African Khoisan) were largely replaced by Bantu-ancestry populations over the past 2,000 years, though with variable admixture. The timing of this replacement closely follows the linguistic and archaeological evidence for Bantu arrival in each region.

The eastern Bantu expansion produced some of Africa's most widely spoken languages. Swahili, a coastal Bantu language enriched by centuries of Indian Ocean trade, became East Africa's principal trade language and is now spoken by approximately 200 million people. Zulu and Xhosa, southernmost Bantu languages with distinctive click consonants borrowed from contact with Khoisan languages, are among South Africa's official languages. The Bantu expansion's demographic impact on Africa rivals the Indo-European expansion into Europe and the Austronesian dispersal across the Pacific as one of the defining demographic events of the Holocene.