What were
Hunter-gatherers

Hunter-gatherers were people who lived very early in times of human civilization when we didn't have any permament settlements yet, nor have we invented agriculture either. 

Hunter-gatherers lived through animal hunting, foraging, and other types of resource depletion of a certain area. When they depleted all the resources (killed most of the animals, and ate most of the berries for example), they moved to another place. 

Ghana, first of the great medieval trading empires of western africa (fl. 7th–13th century). it was situated between the sahara and the headwaters of the sénégal and niger rivers, in an area that now comprises southeastern mauritania and part of mali.