A continent once known more for witchcraft than worship has become a stronghold - and a flash point - for the world's two largest religions, the Pew Forum said in a survey released Thursday.
With more than 90 percent of the region's population saying faith is "very important" in their lives, it's also on one of the major fault lines of religious conflict.
Northern Africa is heavily Muslim and southern Africa is mostly Christian but where the two religions meet in a 4,000-mile belt from Somalia to Senegal has often turned violent, especially in Nigeria, where hundreds of Muslims and Christians have died since January fighting each other.
At least 45 percent of the Christians surveyed in Ghana, Zambia, Mozambique, Cameroon, Kenya, Uganda and Chad - which topped the list at 70 percent - consider Muslims to be violent. Far smaller percentages of Muslims see Christians as violent - Djibouti had the largest percentage at 40 percent, followed by Kenya and Uganda in the low 30s.
"Christians are less positive in their views of Muslims than Muslims are in their views of Christians," senior researcher Greg Smith said, adding that both Christians and Muslims also showed concern about extremism within their own ranks.
The massive survey, called "Tolerance and Tension: Islam and Christianity in Sub-Saharan Africa," charts how a region that gave birth to the term "global South" is a world leader in religious practice.
From December 2008 to April 2009, the Pew Research Center's Forum on Religion and Public Life conducted 25,000 interviews in more than 60 languages or dialects in 19 countries to ascertain the state of belief and practice among 820 million people in one of the world's most religiously volatile regions.
The survey had input from scholars at Princeton University, Boston University and the Johns Hopkins School of Advanced International Studies. Depending on the country surveyed, it has a margin of error ranging from four to five percentage points for overall answers, and from four to 10 points for answers within the religion.
A century ago, the bulk of world Christianity was concentrated in Europe and in the Western Hemisphere. Today, 20 percent of the world's Christians now live south of the Sahara Desert. Islam, which was concentrated in sub-tropical countries to the north and east of Africa, now has 15 percent of its worldwide adherents living there.
"It is fascinating to probe the question of why the expansion has happened and the why of the forces behind it," Mr. Smith said.
"There's a high percentage of Christians and Muslims in every country who say they are committed to spreading their faith and winning converts over to their side. It's that commitment at the grass-roots level by Christians and Muslims that is a driving factor."
And Africa, he added, "is the only continent in the world where you have a roughly equal division of the two largest religions in the world."
According to the World Religion Database, 48 percent of Africa's 1 billion inhabitants are Christian (495.8 million); 41 percent are Muslim (423.5 million) and 11 percent are "other" or unaffiliated.
South of the Sahara, Muslim adherents have gone from 11 million in 1900 to 234 million in 2010; Christians have gone from 7 million to 470 million.
A century ago in Sub-Saharan Africa, animist religions made up the bulk of the population with less than one-quarter adhering to either Islam or Christianity.
Now less than 13 percent of the population follows the traditional religions while conversion rates to Islam and Christianity have skyrocketed. Only Liberia reported more than 10 percent of the population as still embracing traditional religions.
"It's clear, from what other studies have shown, that Islam has spread from the north on down and Christianity has spread from the south and the coasts inward through a combination of missionary activity and independent African activity," associate researcher Alan Cooperman said. "African-initiated churches are quite active and have been independent of missionary activity for a long time."
But both faiths are highly syncretistic. More than half the people surveyed in Mali, Tanzania, Senegal and South Africa believed that sacrifices to spirits will protect them from harm. One-quarter of the Muslims and Christians surveyed in several countries said they believed in the power of charms or amulets to protect them.
Large majorities of both religions said they would like governments based on biblical or Islamic sharia law in contrast to the governments they currently live under. Christians in Zambia (77 percent) ranked the highest in favoring biblical law. Muslims in Djibouti (82 percent) ranked highest in desiring sharia law.
Although Christian mission work to Sub-Saharan Africa has been ongoing since Franciscan and Dominican monks' arrival in the 15th century, bolstered by Protestants in the mid-18th century, the chief form of Christianity is Pentecostal, researchers said.
In Nigeria, Ethiopia, Ghana and Liberia, one-quarter of all Christians belong to Pentecostal denominations that emphasize the supernatural "gifts of the Holy Spirit" such as healing, prophecy and praying in tongues. Even members of other Christian denominations, the report added, embrace Pentecostal practices.
More than half of the Christians surveyed believe Jesus Christ will return to rule the Earth in their lifetimes. Majorities also believe in the "prosperity gospel;" that God will give health and wealth to people if they have enough faith.
Similar attitudes were common among Africa's Muslims: About one-third said they expect the restoration of the caliphate - worldwide Islamic rule - in their lifetimes.
More than half of the Muslims surveyed said society as a whole - not individual women - should decide on whether to wear the veil.
Although Muslims often get blamed for allowing female "circumcision," which is the mutilating of female genitals, the practice is more common among Christians than Muslims in Uganda and Nigeria. However, the highest rates of female circumcision are in the majority Muslim countries of Mali and Djibouti.
Muslim expansion historically came through Islamic traders but in more recent decades, Islamic governments, particularly Saudi Arabia, have spent billions of dollars building mosques and Islamic centers in Africa. Examples include the King Faisal Center in NDjamena, Chad; the Islamic Center in Abuja, Nigeria; the Islamic African Center in Khartoum, Sudan; the Islamic Solidarity Mosque in Mogadishu, Somalia; four mosques in Gabon and two in Burkina Faso; the Zanzibar Mosque in Tanzania; and the Grand Mosque in Senegal.
With most of the populations adhering to one or the other religion, chances are, surveyors said, that neither religion will keep up its current growth rates as the pool of potential converts has shrunk.
Neither religion seems to be converting members of the opposing religion in great numbers, they added, with the exception of Uganda where 32 percent of the respondents who were raised Muslim now say they are Christian.