The continent of Africa is home to many indigenous religions: Vodun, Ifá, Badimo, Dini Ya Misambwa, Ọdinani, and countless others. A century ago, these were the dominant faiths across the continent, but today, only about 10% of Africans practice an indigenous religion.
Source: Matthew White – http://users.erols.com/mwhite28/afrorelg.htm
I think you may have misunderstood the African Religious Systems. Firstly, Christianity was well established in Africa before the Islamic Religion. Remember, Mohammed came after Jesus Christ. But you are correct about the pagans of Europe, the literature fully documents that. The Apostle Paul conversation with the congregation on Mars Hill demonstrates the worship of so many gods, that they built an altar to the unknown God. And he taught them about this unknown God. And
what we know states that, Ancient Civilization and all three major world religions began in the Nile Valley; and there are indigenous fraternities in parts of Africa today, that refer to their uninitiated persons as sinners and their initiated persons as Christians long long before European colonizers set foot on the Continent.
Lord McCauley spoke about his African experience to the British Parliament on February 2nd 1835, when he said, “ I have traveled across the length and breadth of Africa and I have not seen one person who is a beggar, who is a thief such wealth I have seen in this country, such high moral values, people of such caliber, that I do not think we would ever conquer this country, unless we break the very backbone of this nation which is her spiritual and cultural heritage and therefore, I propose we replace her old and ancient education system, her culture, for if the Africans think that all that is foreign and English is good and greater than their own, they will lose their self esteem their native culture and they will become what we want them, a truly dominated nation”,
The quote is fictional, and usually has “India” in place of “Africa”.
This map doesnt fully represent religion in Africa. Islam and Indeginous religions were the majority in Africa way before the mass colonization period in the mid 1500s dating back to the days of Mansa Musa in the 1300s.