What elements of the landscape impacted where civilizations developed in africa? (need by )

Initially it was the Valley of the Nile the environment where historical civilizations developed, in contact with those of the ancient Near East, from the Egyptian civilization. The expression Nilotic civilization or Nilotic civilizations is used to include the Nubian civilization.  

Subsequently developed in North Africa, the Carthaginian civilization; and in sub-Saharan Africa the African kingdoms or empires (also called classic African civilizations or the classic African period). Fundamental facts were the incorporation of North Africa to the Roman Empire and, already in the Middle Ages, the expansion of Islam. As autonomous civilizations the Christian Ethiopia (or Abyssinia, one of the possible locations of the legendary kingdom of Prester John) and the animists survived. The era of discoveries and the European colonization of Africa ended up making the entire continent a space subject to acculturation, and integrated into Western civilization. The processes of decolonization of the mid-twentieth century and the ideologies of Third Worldism, Blackness and Pan-Africanism did not imply real independence, especially in the economic and cultural (neocolonial).