About 1960, the study of West African history took a new turn as historians became aware of the interest and value of Islamic sources for their work, particularly manuscript materials in Arabic. To be sure, the use of Arabic sources for the history of West Africa is nothing new: in 1841, W. Des-borough Cooley published his The Negroland of the Arabs Examined and Explained; or, an Inquiry into the Early History and Geography of Central Africa. But Cooley's pioneering book was discounted by later British and American writers on Africa as the work of an eccentric. In the 1880's and 1890's, many of these writers were spellbound by their vision of what Christianity might do for the African, while others were preoccupied by what they deemed to be the morally indefensible activities of the Muslims as slave-raiders and traders in West and East Africa. As late as the 1930's, the well-known British anthropologist C. K. Meek indicted Islam in northern Nigeria when he wrote: “The institution of slavery is a pivotal feature of Islamic society, and we are justified with charging Muhammadanism with the devastation and desolation in which Northern Nigeria was found at the beginning of this century.” Other writers, like Sir A.C. Burns for Nigeria, and A. W. Cardinall and W. E. F. Ward for Ghana, dismissed the Islamic side of West African history in few words, or gave it no mention at all. There were other reasons for this lack of emphasis. In northern Nigeria, for example, many British officials were apprehensive of an outbreak of “Mahdism” among the Muslims; and very frequently, French officials looked on Islam as a rival political system, dangerous and potentially subversive.