SAN
Once the San roamed over most of the African continent...

Once the San roamed over most of the African continent.  Certainly they were living in the Kalahari and Tsodilo Hills as far back as 30,000 years ago, as archaeological finds in the Kalahari have demonstrated.  Some linguists even credit them with the invention of language.*  

​        *This caption is from Botswana and Namibia and Southern Africa -- Lonely Planet's travel guides.