This equilibrium came to end during the Mfecane period, 1823–1843, when a succession of invading peoples from South Africa entered the country.
Although the Bangwaketse were able to defeat the invading Bakololo in 1826, over time all the major chiefdoms in Botswana were attacked, weakened, and impoverished.
These proto-Kalanga were closely connected to states in Zimbabwe as well as to the Mapungubwe state.
These states, located outside of current Botswana's borders, appear to have kept massive cattle herds in what is now the Central District—apparently at numbers approaching modern cattle density.
Only after 1843, when the Amandebele moved into western Zimbabwe, did this threat subside.
Both speak Khoisan languages and hunted, gathered, and traded over long distances.
When cattle were first introduced about 2000 years ago into southern Africa, pastoralism became a major feature of the economy, since the region had large grasslands free of tsetse fly.
Botswana is a member of the African Union, the Southern African Development Community, the Commonwealth of Nations, and the United Nations.
The country has been among the hardest hit by the HIV/AIDS epidemic.