What is isithembu?.#isithembu means polygamy or being in a polygamous marriage (A marriage of having more than one wife ) and it is a custom in many parts of Africa. isithembu (also called Sethepu) is the African custom of a man being able to have more than one wife at the same time.There were and are several situations or Reasons that allow a man to have additional wives. This custom is mainly done by Kings in Africa A man may marry again for reasons that current wife or wives cannot bare c