The Muslim religion appears in the 7th century of the Christian era. In a hundred years, it spread quickly to the whole of the Mediterranean basin by the intermediary of the Arabs who conquered North Africa populated for a long time by the Berbers; they extend to the Iberian Peninsula ruled by Germanic peoples; the Arabs also integrate western Asia and defeat the Byzantines and Sassanid Persians. These regions are therefore diverse in terms of their population. They are in part unified by the Arab-Muslim culture; they use Arabic and the dinar in commercial transactions. After the fall of the Umayyad dynasty (750), the Muslim world was divided into several political entities (caliphates, emirates, sultanates) often rival.