Since agriculture began farmers have selected, used, exchanged and transported planting materials over short and long distances, and natural selection has also worked on these plants. As a result it is difficult to assemble information on the origin and evolution of agricultural crops, including sweetpotato.

Oral and written histories and molecular markers are used to try and trace the origins of different crops. Sweetpotato (Ipomoea batatas (L.) Lam.)  It did not originate in Africa, it was domesticated at least 5,000 years ago in tropical America. Central America is believed to be the centre of origin of sweetpotato, with it being brought to Africa by Portuguese traders in the 16th Century. It was probably introduced on both the east and west coasts of Africa (possibly Angola and Mozambique), and then spread inland. Further introductions from India to East Africa occurred later under British colonial influences. Sweetpotato was already widely grown from Zanzibar to Egypt and used as food and for making beer by the time of the Speke-Grant expedition in the 1860s.

Today, sweetpotato is the seventh most important food crop in the world. In 2011, about 8 million of the world’s agricultural land was used to grow sweetpotato, and over 95% of the world’s sweetpotato output was from developing countries.

In Africa, sweetpotato is particularly important in countries surrounding the Great Lakes in East and Central Africa; Malawi, Angola, Mozambique and Madagascar in Southern Africa, and Nigeria in West Africa.