Whether the local populations engaged in animism, polytheism, or other cultural heritage-derived beliefs, once Africa was directly invaded by the Turks and subsequently opened up by European traders, the Islamic religion became prevalent. The scope of this paper is to focus on the advent of the Islamic faith within the region and explain some of the factors that contributed to it. These factors can be generalized within three broad areas; geographical, historical, and behavioral. Through the combination of these causes, Islam became prolific and replaced much of the ancient indigenous practices. Africa is a diverse continent where the geography includes almost every possible landmass variation. From desert, tropical forests, mountains, and the plains of the savannah, the influence of the geography itself impacted how and when Islam spread. As Parrinder points out in his article, the expansion of non-native populations tended to take a vertical shape, almost assuredly due to the use of the coastlines as entry points for foreign traders, but the land itself is stratified horizontally between the major geographical components. "These two ways of viewing the country help to explain the progress of Islam; for it came into the interior plateaus first and long remained almost stationary there, cut off from the coastal regions by the impenetrable forest" (Parrinder 131). It wasn't until the European traders established a transportation infrastructure of roads and railways that Islam began to make inroads from the interior of the country into the coastal regions. Once that was accomplished, however, Islam was able to spread from the central portions of the continent to the outer edges, including West Africa. This specifically points to the first of three historical aspects of the spread of Islam.
While it might be inferred that Islam was initially carried into Africa by the Turkish invaders who used the Mediterranean Sea as a conduit for expansion, the fact is that the spread of Islam owes its initial developments to commerce. As Trimingham notes, "Islam was first introduced into West Africa by traders. Their activities in purveying Islam along with their goods have continued ever since" (28). It is intuitive that religion spreads with commerce. As native people interact with merchants, there is a blending of ideas and philosophies that naturally takes place. Given the aggressive proselytization practices of Islam, there is no great mystery as to why the native Africans would convert. Their assimilation into Islamic beliefs was also fostered by the historical imperialism of the religion.
By its very structure, Islam is a faith that blends political and economic activities with religious practice. Once the belief system becomes sufficiently popular, it begins to enforce its tenets through more than simple missionary means. The statement that "Islam in power is secularized theocracy and this always leads to forms of religious imperialism" (Trimingham 28) is as true today as it was in the eleventh century. Once entrenched in tribal governance, the more aggressive forms of an imperialistic recruitment would emerge. These practices included everything from forced conversions to the refusal to allow commerce between individuals of the faith and apostates. In many parts of Africa, conversion to Islam was not a voluntary activity, but a political and economic necessity. The next historical fact, that of western development, would simply provide the means for expansion of the imperialistic