The aboriginal peoples of southern Africa, collectively known as San, suffered widespread genocidal violence as a result of colonial invasion from the eighteenth century onwards. Being hunter-gatherers and racially stereotyped as among the lowest forms of humanity, they were targeted for mass violence by colonial states and civilian militias. The first case study in this chapter analyses exterminatory Dutch and British violence against San in the Cape Colony during the eighteenth and nineteenth centuries. The second examines the obliteration of San society in Transorangia by indigenous Griqua polities during the early nineteenth century, cautioning against the over-simple, racialised binaries that often inform studies of frontier strife. Thirdly, from the mid-1840s onwards after the British annexation of Natal, conflict with San communities in the midlands resulted in their eradication by 1870. The fourth case study outlines how South African forces halted the German genocide of Namibian San when they invaded German South West Africa in 1914. The final case reveals a different pattern. It explores how late-nineteenth-century white pastoralists established peaceful relations with San in western Bechuanaland.