"There's nothing really to compare with the growth of Christianity in Africa. As far as we know it's a fairly unique phenomenon," says Jonathan Bonk, editor of the US-based International Bulletin of Missionary Research.
Reliable statistics are hard to come by, but IBMR estimates there were 8.7m Christians in Africa in 1900, rising to 117m by 1970 and 389m today. The most recent phenomenon is a rising wave of evangelism, driven by Africans and westerners - mainly Americans - that is sweeping across the continent.
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There are now Africans coming to the United States to do missionary work, instead of the other way around. Most notably, the conservative faction breaking away from the Episcopal Church in the United States is sponsored by an African wing of the Anglican Church. Africa has also become a conservative stronghold within the Catholic Church. I have an Aunt and Uncle who spent years as African lay missionaries for the relatively staid Evangelical Lutheran Church in America, and the intensity of African involvement in and commitment to their local Christian churches is almost unthinkable for an American in a mainline American denomination.
In Europe, in contrast, secularism is the uniform trend. Weekly church attendance in Ireland, one of the most devout countries in Europe is down almost 30% in thirty years. In the Netherlands, France and Sweden church attendance has fallen below 10% (the United States by comparison has roughly 40% church attendance on a weekly basis).
In 1900, almost everyone in Europe was Christian. Now, three out of four people identify themselves as adherents to Christianity. At the same time, the percentage of Europeans who say they are non-religious has soared from less than 1% of the population to 15%. Another 3% say they don't believe in God at all, according to the Center for the Study of Global Christianity.
In 12 major European countries, 38% of people say they never or practically never attend church, according to the World Values Survey in 2000. France's 60% non-attendance rate is the highest in that group. In the USA, only 16% say they rarely go to church.
Neither the African, nor the European trend, have ends in sight. They will continue for, at least, another generation. The only full places of worship in London are immigrant churches and mosques, and unlike other churches in Europe, in these places of worship a large share of the members are young.
The United States is not decisively a part of either trend and shows strong regional variations. According to the Catholic sponsored study (one of the two most comprehensive in existence) called Glenmary:
Utah (74%) and North Dakota (73%) have the largest percent of people claimed by [religious denominations]. The District of Columbia is also at 73%. Oregon (31%) and Washington (33%) are at the bottom of the list.
States differ not just in nature of religious preferences, as well as the extent of religious participation:
Catholics have the largest number of adherents in 37 states and the District of Columbia. The Southern Baptist Convention has the largest number of adherents in 10 states, all in the South. The Church of Jesus Christ of Latter-Day Saints has the most adherents in Idaho and Utah, and the United Methodists have the most adherents in West Virginia.
Catholics are one of the four largest groups in every state of the union as well as in the District of Columbia. United Methodists are one of the top four groups in 38 states, and Southern Baptists make the top four in 28 states and the District of Columbia. The Latter-Day Saints and Evangelical Lutheran Church of America are both among the top four in 13 states, and the Jewish adherents are in the top four in 10 states and the District of Columbia. Twelve other groups make the top four in anywhere from one to eight states.
Much of the American Midwest and Northwest is dominanted by Lutheran and Catholic churches with their origins in Europe. Both of these churches are scarce in most of the South, were Baptists and other evangelicals dominate the religious scene. The Mormons are a leading church (behind Catholics) in much of the West, not just Utah and Idaho.
According to the American Religious Identification Survey, the other major national study of religious preferences in the United States, modest declines in overall religious participation in the United States are accompanied by significant shifts from one part of the religious landscape to others. Most mainline denominations are stuggling, as is Judaism. They are losing members both to evangelical trends and to secularism. White Catholicism tends to mirror mainline denominational trends (and political trends), while church growth among Hispanic Catholics hides the mixed trends facing the Catholic church. Evangelical denominations are at least holding steady and many of the most charismatic are growing. Non-denominational but evangelical leaning independent churches, and every manner of non-Christian faith other than Judaism (including the ranks of the non-religious), are growing quickly.
The shifting trends in the religious preferences of Americans and Europeans, at least, has important influences on the political and social trends there (in Africa political chaos and a lack of democracy in many countries makes it hard to tell). In Scandinavia, unmarried parenthood has become the norm, and fewer people are having children. But, despite claims the Christianity has been replaced by Materialism in Europe, Europe remains far more committed to less material concerns like the security of a social safety net and leisure, than the far more religious United States. The "culture wars" in American politics do match up to the religious map of the United States. The religious right that drives the Republican party is a minority religious preference in the nation as a whole. But, in many states it is virtually synomous with the regional culture and, of course, "all politics are local."
There is one general rule that helps explain, a little, at least, these trends. Churches thrive when they preserve a threatened culture and wilt when the culture they are embedded in is not at risk.
Why is church participation six times as great in Ireland as it is in Sweden, yet falling? Because the Catholic Church in Ireland spend half a millennium protecting Irish culture from British imperialism, a culture which is now more secure than ever as Ireland has gained independence and the religious conflicts in Northern Ireland have grown subdued. In contrast, the Swedish Lutheran Church was the established church for half a millennium (it was disestablished in 2000) and thus never needed to protect the local culture. The fact that the vast majority of European Christians are members of established churches which almost by definition do not involve threatened cultures again explains their declines.
In the United States, mainstream American culture is the culture of New York and Los Angeles, and more generally the North. This is not a new development. The North has been beating the South in the culture wars since, at least, the Civil War. Broadcasters speak in the accents of Ohio, not Georgia. The application of the Bill of Rights by the U.S. Supreme Court to the states that has taken place for the past several decades has been one loss after another for the South. Most Southerners don't believe in the fundamental idea behind the establishment clause of the First Amendment. They have grave doubts about many kinds of free speech from obsensity to political dissent that they see as aiding our nation's enemies. They are incensed by the protections it affords to criminal defendants. Their notions of what is cruel and unusual are considerably less merciful than those of the rest of the nation or the world at large. Nashville and Memphis, the cultural centers of Country-Western culture, live in the shadow of their coastal Northern counterparts. The dominant national attitudes towards gender and race, many of which are enshrined in law in the Civil Rights era, were enacted over the fierce opposition of the South. The gay rights movement adds insults to those injuries from its perspective.
Why does all of this matter? Because, Southern culture is threatened, and its religious fervency, to a great extent, can be explained by the fact that churches, especially its evangelical ones, are the caretakers of that culture. Failing to support Southern Churches, in the face of a sustained assault from national institutions governmental and private alike, is to sound the death knell of that culture. The African American community faces very different threats to its culture, but the threats are definitely there and likewise drive the vitality of black churches. In contrast, mainline Christian churches preach a creed shared by the dominant Christian culture. The Lutheran Church is not the dike that is holding back national threats to the way of life of the typical resident of Seattle.
This general rule also explains lots of other mini-trends. Why are immigrant churches so vibrant? Because they preserve the culture of the home country. Where are atheist groups most well organized in Colorado? In Colorado Springs, home to Focus on the Family and capital of the Christian Right.
Why are we seeing a wave of Islamic fundamentalism? Because Western modernity is dramatically overhauling the culture of every predominantly Islamic region in the world, dragging hundreds of millions of people through what Europe experienced as centuries of incremental cultural change in a couple of generations.
I don't have textured enough information to really know what is going on in African Christianity, but I suspect that the same principle turns out to be at work.