LAGOS, Nigeria - Winding its way across Africa is an invisible fault line between a mainly Muslim north and a majority Christian south.
Across this front, somewhere in the scrubland south of the Sahara Desert, tensions flare between increasingly strident Christian movements aggressively working to convert people of other faiths and an Islamic world wary of encroaching Western influences.
When the two worlds collide — a Muslim takes offense at a woman showing too much skin or a shop selling alcohol, a Christian takes umbrage when a thief’s hand is chopped off — entire villages can riot.
Fighting for souls
Africa’s nearly 900 million people offer the largest field of potential converts anywhere in the world, and the competition for souls is fiercest between the continent’s two biggest religions — Catholicism and Islam.
Catholicism, with an estimated 136 million African followers, is the most important branch of Christianity on the continent. Thus, the challenge for Pope Benedict XVI will be to calm Africa’s religious tensions, trying to bridge a gulf of distrust fostered by extremists on both sides.
“The Vatican recognizes that in sub-Saharan Africa you have the area where Muslims and Christians are most likely to be confronting each other,” said John Voll, director of the Center for Muslim-Christian Understanding at Georgetown University.
“It is a high priority to make sure that those Catholic interactions with Muslims don’t necessarily lead to open conflict.”
The crusades continue
But the ancient battle has exploded across an invisible border that separates not just religions but also cultures and major ethnic groups and ancient divisions between herders and settled farmers.
The 21-year civil war that recently ended in Sudan erupted when the Arab government imposed strict Islamic law opposed by blacks in the south, where more than 4 million Catholics make up 13 percent of the population. That war is blamed for more than 2 million deaths.
Tens of thousand of others have been killed across religious fault lines during conflicts in Liberia, Ivory Coast and Nigeria, whose estimated 20 million Catholics are outnumbered on the continent only by Congo’s 28-million-plus co-religionists.
Sect trumps tribe
The decision by British colonizers to rule northern Nigeria through Muslim emirs while Irish Catholic missionaries proselytized in the south has produced a nation where tribal divisions are transcended only by religion. The nation of 126 million people is roughly evenly split between Christians and Muslims.
Across Africa, Islam and Christianity are both estimated to have about 400 million followers, with animists making up most of the remainder.
In Nigeria, riots erupted in 2000 when mainly Muslim northern states instituted Islamic law, including punishments of amputation and death by stoning. In 2002, more than 200 people died in Christian-Muslim riots triggered by opposition to holding the Miss World competition in Nigeria.
Jihad or alliances
This month, Nigerian newspapers have been full of reports that Islamic leaders are preparing a jihad, which they deny. Islamic leaders, meanwhile, complain that Muslims are being marginalized under a southern Christian president who ended 20 years of northern rule.
Pope John Paul II chose Nigeria’s most powerful cleric, Cardinal Francis Arinze, to lead the church’s rapprochement with other religions at a time when fundamentalist Islamic and Protestant sects replaced communism as the biggest challenge to Catholic proselytizing.
Cardinal Arinze stressed the common battle by Islam and Catholicism against sexual permissiveness and contraception.
Extremists gain strength
“Authentic dialogue demands that Muslims and Christians accept one another with all their similarities and differences,” he told students at Georgetown University in 1993.
He added: “Muslim-Christian relations are challenged and obstructed by religious fanaticism or extremism.”
More extreme forms of Christianity and Islam are gaining strength in Africa, raising the risk of more confrontation, especially as the two sides compete for converts from each other’s camps as followers of traditional animist religions shrink.
The Rev. Matthew Hassan Kukah, an influential Nigerian Catholic priest, reserves his most trenchant criticism for evangelical Christians rather than Muslims, saying they are promoting a materialist view of Christianity and stoking tensions by behaving “as if they were out to convert everyone.”
Muslims have rioted when evangelical churches held football-stadium gatherings.
“There is too much aggressive evangelization,” said Latif Adegbite, secretary-general of Nigeria’s National Supreme Council for Islamic Affairs.
But Islam is also on the march, and today the religious boundaries on the continent are shifting south.
“The Catholic Church has become aware that Islam has become a serious alternative” in central and well as West Africa, said Mr. Voll. To face competition from Islam, he said, the church will need to “reconstruct itself as a refuge for people in times of social crisis.”
Genocide in Rwanda
The Catholic Church failed that test during the 1994 genocide in Rwanda, where some churches that offered sanctuary were turned into slaughterhouses and some Catholic priests participated in the killings.
John Paul refused to apologize, saying the church could not be blamed for the actions of individual priests.
Islam offers a route more compatible with African tradition, especially by allowing polygamy. Some Catholic Africans marry their first wife in church, then take second wives in traditional ceremonies.
AP reporters Michelle Faul in Dakar, Senegal, and Rodrique Ngowi in Nairobi, Kenya, contributed to this report.