For fifty years, until the Arabs to keep the unity, they conquered one country after another. Then came the religious disputes and wars between the followers of Islam. Soon on the scene of history came the new conquerors - the Turks. However, they, and part of the Mongols, was in the sphere of Islam, the religion assimilated and became zealous Muslims. The strength of Islam - its proximity to the tribal consciousness. Since the flight of Muhammad and his followers from Mecca to Medina, Islam requires only obedience. It replaces the tribal law of another, but also arranged, as covering the whole life of a simple system requirements: five times a day pray, let him do something, do not do that, then ... It is this simplicity facilitates the spread of Islam among the nomads in the Middle Ages and gives it an important advantage over Christianity in contemporary Africa.