It is uncertain when Islam began to penetrate the “western Sudan”: for a review of the evidence, reference may be made to the earlier chapters of Bovill's Caravans of the old Sahara. That the age-old north to south and west to east trade routes (carrying outwards gold and slaves, inwards cloth and manufactured articles, internally dates and salt as the main articles of commerce), provided the vehicle can be in little doubt, as also that, by the fourth century a.h. if not earlier, appreciable Moslem influence had begun to work in the area shown on modern maps as northern Nigeria. In this area Arabic is not a tongue spoken, save in dialect by the numerically insignificant tribe of Shuwas in the northeast. But with the spread and pre-eminence at first cultural and later political of Islam, written “classical” Arabic, which provided the only means of a literary education became the medium of diplomacy, commerce, and correspondence. This position it maintained until a few years ago, suggesting a parallel to the use of Latin in medieval Western Europe. Yet, so far as is known, although original works were produced farther north in the Sahara proper, until the “reforming” Fulani jihad at the end of the eighteenth century a.d. (active operations began 21.2.1804), few original compositions in Arabic emerged. The stimulus of this jihad appears, among other results, to have evoked the nucleus of an original indigenous Arabic literature, none of which has been printed or translated, save a few historical documents.