Such personalities, more effectively perhaps than any other factors, engender national unity and bring it to a high pitch. There are regions in which the other main conditions of national unity have long obtained, but which have failed to become the seat of any enduring nation. Although the greater part of Africa, perhaps the richest continent of the globe, has been in the possession of the negro races during all the ages in which the European, Asiatic, and American civilisations were being developed, those races have never founded a nation. Nevertheless many, perhaps most, negroes are capable of acquiring European culture and of turning it to good account. And, when brought under the influence of Arabs or men of other races, they have formed rudimentary nations[71]. The incapacity to form a nation must be connected with the fact that the race has never produced any individuals of really high mental and moral endowments, even when brought under foreign influences; and it would seem that it is incapable of producing such individuals; the few distinguished negroes, so called, of America—such as Douglas, Booker Washington, Du Bois—have been, I believe, in all cases mulattoes or had some proportion of white blood. We may fairly ascribe the incapacity of the negro race to form a nation to the lack of men endowed with the qualities of great leaders, even more than to the lower level of average capacity. On the other hand, there is at least one people which, in the absence of every other condition, has continued to retain something of the character of a nation for many generations—namely, the Jews. The Jews are not even racially homogeneous, and they are scattered through all the world under the most varied physical conditions; yet the influence of a succession of men of exceptional power, Moses and his successors the prophets, all devoted to the same end—namely, the establishment of the Jewish nation and religion—has lived on through many generations and still holds this people together, marking it off from all others. This is an extreme instance. But another almost equally striking case is that of the Arab nation, which has owed its existence to one man. The Arab nation was made by the genius of Mahomet, who welded together, by the force of his personality and the originality and intensity of his religious conviction, the warring idolatrous clans of Arabia. Until his advent these had been a scattered multitude, in spite of racial and geographical uniformity, geographical isolation, and fairly free intercommunication. We have here one of the purest, clearest instances of the effect of great personalities in furthering nationhood; for there seems to be no reason to believe that, if Mahomet had not lived, any such development of the Arabian people would have taken place.