no A TROPICAL DEPENDENCY muted for payment of a subsidy ; but historians are practically in agreement that the conversion of the northern belt of the Soudan to Mohammedanism became general at about this date. The Almoravides did not confine their requirements to a purely nominal conversion. Doctors of divinity and Moslem teachers were sent into the black countries to teach the true faith, and no doubt the increase of communication which at this time took place with Spain opened the way for the acceptance of more enlightened religious views.

Although the cordon of natives spoken of by Ibn Khaldun in the fourteenth century extended at that period as far eastward as the Nile, the march of Abou Bekr in the eleventh century does not appear to have been carried beyond the deserts lying to the north and northeast of the Bend of the Niger. The Berber nations which completed the cordon are distinctly stated by other writers to have come down from Tripoli and the East.

Two important political incidents marked the campaign of Abou Bekr. In 1076 he carried the vengeance of Audoghast to the gates of Ghana, and, overthrowing the reigning black dynasty, placed a Berber on the throne. The life of the country does not seem to have been profoundly affected at the time by this revolution. El Idrisi, writing nearly a hundred years later, still speaks of it as being the greatest kingdom of the blacks. He mentions the fact that it is ruled by a king of Berber descent, who " governs by his own authority, but gives allegiance to the Abbasside Sultan of Egypt," and that the king and people are now Mohammedans ; but he does not speak of it as having become in any respect a Berber kingdom.

Here is his account : '* Ghana ... is the most considerable, the most thickly populated, and the most commercial of the black countries. It is visited by rich merchants from all the surrounding countries, and from the extremities of the West. Its inhabitants are Mussulman. . . . The king governs by his own authority, but he does obeisance