Stories published in the sober British medical journal The Lancet don’t normally inspire sensational headlines. But one recent piece on current and future trends in global fertility has called forth some stunned and stunning reactions. The article describes what the BBC terms a ‘Jaw-Dropping’ Global Crash in Children Being Born, as most areas of the world move toward what we thought of (until recently!) as very low Danish-style fertility rates. In the words of researcher Christopher Murray, “I think it’s incredibly hard to think this through and recognize how big a thing this is; it’s extraordinary, we’ll have to reorganize societies.”
Arguably, this is one of the most significant trends facing the world in the coming century.
Although The Lancet article didn’t touch on matters of religion, that is, in fact, one of the arenas most affected by this shift. Last year, in an article I wrote for TGC, I discussed the intimate relationship between fertility rates and levels of religiosity. That’s now the subject of my new book, Fertility and Faith: The Demographic Revolution and the Transformation of World Religions (Baylor University Press). Briefly, I argue that societies with high fertility rates have high levels of religious faith and practice, while declining fertility correlates closely to shrinking institutional faith, and to secularization. Let me stress, this doesn’t necessarily mean a decline in actual belief, but rather in expressions of faith: believing can continue after belonging has all but vanished.
I won’t repeat my argument about why those phenomena should be linked—see my earlier article—but the model works well around the world, and applies to all faith traditions. Tell me the fertility rate of a particular nation, and I can make a reasonable assessment of the strength or weakness of institutional faith in that society.
Although we can track fertility in various ways, we commonly use the total fertility rate (TFR), which measures the average number of children who would be born to a woman over her lifetime, assuming she survives to the end of her reproductive life. If that TFR figure for a particular country is around 2.1 children per woman, then the population will remain broadly stable, and that level is termed replacement rate. If the rate is much higher than that, say 4 or 5 per woman, then we will see an expanding population.
Tell me the fertility rate of a particular nation, and I can make a reasonable assessment of the strength of weakness of institutional faith in that society.
A fertility rate below 2.1—what we call sub-replacement—results in a contracting population and an aging society. Those figures have enormous religious consequences. Sub-replacement societies tend to be secular, or are undergoing the process of secularization at a high rate. As the United States rate settles around 1.7—a typical Scandinavian rate—it makes it likely that the country will be moving rapidly toward European religious conditions.
Although the relationship isn’t perfect, we see this trend in the growth of the so called “nones,” those rejecting any identification with a religious tradition or denomination. Already, the number of American “nones” is around a quarter of the population, comparable to the figures for evangelical Protestants or for Catholics.
Fertility, Africa, and the Fate of Christianity
What do these demographic predictions mean for the fate of Christianity? I believe the trends will indeed accelerate the decline of faith in Western societies. But I want to stress another component of these current trends that has received far less attention in media reports: some parts of the world will retain high rates of both fertility and faith in the coming decades. Those regions will increasingly be the global centers of Christianity.
Above all, this means Africa. To return to that Lancet study: “The population of sub-Saharan Africa is expected to triple in size to more than three billion people by 2100.” Already by 2050, a list of the 20 countries with the world’s largest populations will include at least six black African nations: Nigeria, the Democratic Republic of the Congo (DRC), Ethiopia, Tanzania, Uganda, and Kenya. All are still marked by high fertility, with TFR’s far-above-replacement level. Taken together, according to this projection, those countries alone will have more than 1.1 billion citizens.
The impact will be immense. In the words of Christopher Murray:
We will have many more people of African descent in many more countries as we go through this. Global recognition of the challenges around racism are going to be all the more critical if there are large numbers of people of African descent in many countries.
That is true. But think about this in religious terms. Africa has two flourishing and expanding faiths—Christianity and Islam—and both will profit from demographic expansion. These societies continue to be vigorously religious: high fertility is characterized by high faith.
High fertility is characterized by high faith.
One 2015 survey asked respondents whether they felt religious. Atop the list were three African countries—Ethiopia, Malawi, and Niger, all at 99 percent—and all the top 25 nations were located in Africa, the Middle East, or Southeast Asia. Each of these nations reported religious sentiments with response rates of 95 percent or higher. At the other extreme were 23 nations drawn mainly from Europe (14 nations) but with several Asian nations also. When asked about the role that religion played in their lives, Africa produced some of the highest numbers reporting “very important”: 98 percent in Ethiopia, 88 percent in Nigeria, 86 percent in Uganda.
This demographic story also draws the emerging map of the world’s great Christian centers. Already by 2050, Africa will be home to more than a billion Christians, by far the largest concentration on the planet. That doesn’t take African migrants living around the world into account, that mighty Christian diaspora. The rate of numerical change is astonishing—and accelerating. By 2050 a list of the 10 countries worldwide with the largest Christian populations will include several African members, including Nigeria, Ethiopia, the DRC, and Uganda. Between 1900 and 2050, the African share of the global Christian population will have grown from barely 2 percent to more than 33 percent. I scarcely dare to extrapolate those numbers as far into the future as 2100. (Throughout, I’m defining Christianity and Islam in broad terms, without too much concern about theological or denominational specificity.)
Africa’s Demographic Story
Any number of African countries illustrate this story of growth, the main variable being the relative strength of Christianity and Islam. When the 20th century began, the lands that would become the nation of Kenya had a tiny population of 1.5 million, although precise estimates are difficult to come by. That number grew spectacularly. National population reached 10 million by 1966, 30 million by the end of the century, and (probably) 50 million today. By 2050 Kenya could have 95 million people. In religious terms, the Christian proportion of the population has unquestionably swelled since the mid-20th century, to reach a modern figure of perhaps 80 percent or 85 percent. But the increase in raw numbers is staggering—growing from perhaps 4 million Christians in the mid-1960s to more than 40 million today and conceivably to 75 million by the middle of this century. Here, as in all sub-Saharan African nations, levels of religious practice are staggering by the standards of Europe or North America. High fertility, high faith.
Or take Nigeria. In 1900 the lands that became Nigeria had around 16 million inhabitants, of whom a tiny fraction were Christian—perhaps 180,000. That same area now contains almost 200 million people, a figure that could exceed 400 million by 2050. Even if Christians don’t make a single new convert in that land but merely retain their current share of population, then between 2020 and 2050 the number of Nigerian Christians will grow from around 90 million to more than 180 million. At that point Nigeria will be one of the most significant centers of Christianity worldwide. Put another way, between 1900 and 2050, Christian numbers would have grown by at least a thousandfold. Though this is somewhat speculative, the Lancet study offers some predictive power. Nigeria’s population of 800 million may boast 400 million Christians!
In Uganda, Christianity was new in 1900, but has since become the dominant religion. Perhaps 40 percent of Ugandans are Catholic, 32 percent Anglican, and 13 percent Protestant. Muslims make up 13 percent. If, for the sake of argument, we assume that the balance of faiths has held more or less steady, this means that the number of Ugandan Christians has grown from 3 million or 4 million in 1950 to 37 million today, with a possible expansion to more than 80 million by 2050.
As the century proceeds, Christianity will become ever more markedly a religion of Africa and the African diaspora.
Likewise, in 1900, Ethiopia had around 12 million people, rising to 40 million by 1980 and around 100 million today. By 2050 the figure could be 180 million. If we assume that Christians represent around half the total, then the number of Ethiopian Christians will have grown from 6 million in 1900 to more than 90 million in 2050, and, again, that assumes no conversion or evangelism.
Christianity, the African Religion
In 2002 my book The Next Christendom explored Christianity’s shift to the Global South. I suggested that this move would become more pronounced as time progressed. Since the book was written, the main change has concerned the plunge in fertility rates in many nations across Latin America and East Asia, which certainly affects any detailed estimates of Christian numbers.
But what hasn’t changed is my central emphasis on Africa. As the century proceeds, Christianity will become ever more markedly a religion of Africa and the African diaspora. African numerical dominance within the faith will arrive sooner than I argued—and it’ll be more sizable, too.
It’s not just the declines in fertility that are “jaw-dropping”!