Speculations on the Economic prehistory of Africa

Apart from relatively late Semitic influence … the civilizations of Africa are the civilizations of the Hamites, its history the record of these peoples and of their interaction with the two other African stocks, the Negro and the Bushman, whether this influence was exerted by highly civilized Egyptians or by such wider pastoralists as are represented at the present day by the Beja and Somali.…The incoming Hamites were pastoral ‘Europeans’—arriving wave after wave—better armed as well as quicker witted than the dark agricultural Negroes.