Chronological overview after Nurse and Philippson (2003):[1] 1 = 4,000–3,500BP: origin 2 = 3,500BP: initial expansion "early split": 2.a = Eastern, 2.b = Western[2] 3 = 2,000–1,500BP: Urewe nucleus of Eastern Bantu 4–7: southward advance 9 = 2,500BP: Congo nucleus 10 = 2,000–1,000BP: last phaseMap indicating the spread of the Early Iron Age across Africa; all numbers are AD dates except for the "250 BC" date.
The Bantu expansion[3][4][5] was a major series of migrations of the original Proto-Bantu-speaking group,[6][7] which spread from an original nucleus around West-Central Africa across Central Africa, Eastern Africa, and Southern Africa. In the process, the Proto-Bantu-speaking settlers absorbed, displaced, and possibly in some cases replaced pre-existing hunter-gatherer and pastoralist groups that they encountered.
There is linguistic evidence for this expansion – a great many of the languages which are spoken across sub-Equatorial Africa are remarkably similar to each other, suggesting a recent common cultural origin of their original speakers. The linguistic core of the Bantu languages, which constitute a branch of the Atlantic-Congo language family, was located in the southern regions of Cameroon.[8] Genetic evidence also indicates that there was a large human migration from central Africa, with varying levels of admixture with local population.[4][9]
The expansion is believed to have taken place between about 6,000 and 1,500 years ago (approximately 4,000 BCE to 500 CE). Linguistic analysis suggests that the expansion proceeded in two directions: the first (termed the "Western Stream") proceeded south either along the Atlantic coast or following rivers through the Congo rainforest, reaching central Angola around 500 BCE. The second (termed the "Eastern Stream") proceeded east either along the northern fringe of the forest or along the Ubangi River, and reached west of Lake Victoria around 500 BCE. From there, they split into two groups, with one heading west to regroup with the Western Stream, and the other dispersing over Eastern and Southern Africa. The expansion reached South Africa, probably as early as 300 CE.[10][11][12][13][14][15][16]
^Plaza, S; Salas, A; Calafell, F; Corte-Real, F; Bertranpetit, J; Carracedo, A; Comas, D (2004). "Insights into the western Bantu dispersal: MtDNA lineage analysis in Angola". Human Genetics. 115 (5): 439–47. doi:10.1007/s00439-004-1164-0. PMID15340834. S2CID13213447.
^Alves, I; Coelho, M; Gignoux, C; et al. (2011). "Genetic homogeneity across Bantu-speaking groups from Mozambique and Angola challenges early split scenarios between East and West Bantu populations". Human Biology. 83 (1): 13–38. doi:10.3378/027.083.0102. PMID21453002. S2CID20841059.
^Castrì, L; Tofanelli, S; Garagnani, P; et al. (2009). "MtDNA variability in two Bantu-speaking populations (Shona and Hutu) from Eastern Africa: Implications for peopling and migration patterns in sub-Saharan Africa". American Journal of Physical Anthropology. 140 (2): 302–11. doi:10.1002/ajpa.21070. PMID19425093.