In little more than a century, the religious landscape of sub-Saharan Africa has changed dramatically. As of 1900, both Muslims and Christians were relatively small minorities in the region. The vast majority of people practiced traditional African religions, while adherents of Christianity and Islam combined made up less than a quarter of the population, according to historical estimates from the World Religion Database.
Since then, however, the number of Muslims living between the Sahara Desert and the Cape of Good Hope has increased more than 20-fold, rising from an estimated 11 million in 1900 to approximately 234 million in 2010. The number of Christians has grown even faster, soaring almost 70-fold from about 7 million to 470 million. Sub-Saharan Africa now is home to about one-in-five of all the Christians in the world (21%) and more than one-in-seven of the world's Muslims (15%).1
While sub-Saharan Africa has almost twice as many Christians as Muslims, on the African continent as a whole the two faiths are roughly balanced, with 400 million to 500 million followers each. Since northern Africa is heavily Muslim and southern Africa is heavily Christian, the great meeting place is in the middle, a 4,000-mile swath from Somalia in the east to Senegal in the west.
To some outside observers, this is a volatile religious fault line - the site, for example, of al-Qaeda's first major terrorist strike, the bombing of the U.S. embassies in Kenya and Tanzania in 1998, and more recently of ethnic and sectarian bloodshed in Nigeria, where hundreds of Muslims and Christians have been killed.
To others, religion is not so much a source of conflict as a source of hope in sub-Saharan Africa, where religious leaders and movements are a major force in civil society and a key provider of relief and development for the needy, particularly given the widespread reality of failed states and collapsing government services.
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1 The 15% estimate is based on data from the Pew Forum's 2009 report, "Mapping the Global Muslim Population"; other estimates based on data from the World Religion Database. (back to text)
Photo credit: Sebastien Desarmaux/GODONG/Godong/Corbis
Part of the Pew-Templeton Global Religious Futures Project