The Almoravid conquest of ancient Ghana in 1076 AD is certainly among the most dramatic and controversial single events in the historiography of West Africa. It has been regarded as a crucial turning point, as the battle of Hastings was for England, not only for the existence of Ghana, but also for the destiny of the entire area, opening the gates to a triumphant Islam in sub-Saharan Africa.
Yet the conquest and destruction of Ghana by Almoravid invaders constitute one of the myths which still populate African historiography, like the wonderful voyage of Hanno to the Bight of Biafra, which was carried over from classical Greco-Roman texts into modern European literature as early as 1533. Since then the story of Hanno has been used for various purposes by western Africanists, for instance, to explain the diffusion of iron technology into sub-Saharan Africa. Just the same, no definite evidence has yet been found for any Carthaginian sailings along the West African coast, except the Periplus of Hanno itself, which seems to be a literary composition drawn from earlier classical sources. A reason for the popularity of Hanno, and other such stories in African historiography, has been that many modern writers have been content with using the previous secondary literature, instead of examining carefully all the available primary sources. Consequently, many subjective and hypothetical assumptions created by previous scholars, working on the basis of even less evidence, have been transferred bodily from one corpus of research to the next. Finally, their origin forgotten, stories like the voyage of Hanno have become established historical facts through constant repetition in the authorized literature.