How did the geographical concentration of African people change as a result of the African trade route

The arrival of European sea traders at the Guinea coast-lands in the 15th century clearly marks a new epoch in their history and in the history of all of western Africa. The pioneers were the Portuguese, southwestern Europeans with the necessary knowledge, experience, and national purpose to embark on the enterprise of developing oceanic trade routes with Africa and Asia. Their main goals were in Asia, but to reach Asia it was necessary to circumnavigate Africa, in the process of which they hoped, among other things, to make contact with Mali and to divert some of the trans-Saharan gold trade from Muslim North Africa to Christian Europe.