Human burials indicate climate-mediated shifts in South African agriculturalist demography after 2000 years ago

South Africa’s Iron Age (c. 250 CE – 1850 CE) was a period of socio-economic transitions. With the spread of Bantu-speaking peoples from western Africa, the region saw the development of settled agriculturalist societies, the rise of complex chiefdoms, and the development of early states such as Mapungubwe. Questions about how settlements and demographics were influenced by environmental factors are central to the study of this period. Climatic conditions directly impact carrying capacity and agricultural productivity. It is therefore likely that climate variability was an important factor in the success of farming communities, determining food security, population movements, and settlement expansions or abandonments. In this paper we focus on northeastern South Africa and employ the frequency of archaeological human burials and highly resolved palaeoclimate records to assess the relationship between population dynamics and climate change. This reveals significant subregional variability in both human burial frequency and climate change across the subcontinent. Within the subregions, burial frequency shows a positive correlation with humidity, indicating that climatic factors played a pivotal role in shaping the pattern and size of settlements during this period.