The Batswana, a term also used to denote all citizens of Botswana, refers to the country's major ethnic group (called the "Tswana" in Southern Africa). Prior to European contact, the Batswana lived as herders and farmers under tribal rule.
Sometime between 200-500 AD, the Bantu-speaking people who were living in the Katanga area (today part of the DRC and Zambia) crossed the Limpopo River, entering the area today known as South Africa as part of the Bantu expansion.
There were 2 broad waves of immigration to South Africa; Nguni and Sotho-Tswana. The former settled in the eastern coastal regions, while the latter settled primarily in the area known today as the Highveld — the large, relatively high central plateau of South Africa.
By 1000AD the Bantu colonization of the eastern half of South Africa had been completed (but not Western Cape and Northern Cape, which are believed to have been inhabited by Khoisan people until Dutch colonisation). The Bantu-speaking society was highly a decentralized feudal society organized on a basis of kraals (an enlarged clan), headed by a chief, who owed a very hazy allegiance to the nation's head chief. According to Neil Parsons's online "Brief History of Botswana":
"From around 1095 south-eastern Botswana saw the rise of a new culture, characterized by a site on Moritsane hill near Gabane, whose pottery mixed the old western style with new Iron Age influences derived from the eastern Transvaal (Lydenburg culture). The Moritsane culture is historically associated with the Khalagari (Kgalagadi) chiefdoms, the westernmost dialect-group of Sotho (or Sotho-Tswana) speakers, whose prowess was in cattle raising and hunting rather than in farming.