South Africa bears the moniker 'rainbow nation' because of the diversity of its people. There are 11 official languages spread across a large variety of ethnic groups. While the tensions this has caused in South Africa's troubled and violent history are well documented, people unfamiliar with it rarely know the nuances that lie beyond the simplistic black/white skin divide.
Among whites, the Afrikaners and the English are split by language and history. Among blacks, Zulu and Xhosa are the most numerous but the Sotho, Tswana, Pedi, Venda and Ndebele are substantial too. Lengthening the list are less populous cultures such as the Tsonga, Pondo or Swati and the Khoi San, whom colonial ruthlessness nearly wiped out.
If that wasn't complex enough, the Dutch and English brought scores of slaves from Malaysia, Indonesia and India. The mixed race culture referred to as 'coloured' (sometimes called Cape Malay) is a product of their intermarriage with European settlers and indigenous people. Add to that some immigrants both from older (Portuguese, Baltic jews, Italians, Greeks, etc.) and more recent (Zimbabwean, Congoloese, Somali, etc.) waves and the rainbow is complete.
22 years after apartheid, it isn't yet clear whether this social mosaic is a curse or a treasure. What is certain is that if humanity ever finds a way to overcome racial and cultural prejudices, South Africa will have been its greatest testing ground.