Romans in sub-Saharan Africa
Between the first century BC and the fourth century AD, several expeditions and explorations to Lake Chad and western Africa were conducted by groups of military and commercial units of Romans who moved across the Sahara and into the interior of Africa and its coast. However, there was a more significant Roman and Greek presence in modern-day Eritrea and Ethiopia.
Source: Wikipedia — Romans in sub-Saharan Africa (CC BY-SA 4.0)