Over the past two thousand years, Christianity has expanded from a small Jewish sect in the Eastern Roman Empire to become the world’s largest religion. Imperial recognition in the fourth century AD, medieval missionary networks throughout Europe, and later colonial-era missionary activity in the Americas, Africa, and parts of Asia steadily expanded its reach. As of 2020, it still accounts for the largest share of humanity, accounting for 28.8% of the global population, or approximately 2.3 billion people. However, new demographic analysis from the Pew-Templeton Future of Global Religion Project shows that underneath this dominance, a quieter shift is taking place. Christianity is still growing in raw numbers but shrinking in proportion, losing followers in dozens of countries while rapidly expanding in others and shifting geographically from its historic base in Europe to sub-Saharan Africa. The findings, which draw on more than 2,700 censuses and surveys in 201 countries and territories, track religious change between 2010 and 2020 and examine the forces driving this change, particularly fertility patterns and religious “conversions” (people giving up their faith in adulthood).
From imperial religion to global majority
The early spread of Christianity relied on itinerant missionaries and the promise of close-knit communities to provide social support and universal salvation. Its trajectory changed dramatically when Emperor Constantine legalized the faith in 313 AD, and it later became the state religion of Rome. Missionary activities in the Middle Ages brought it to various parts of Europe, and from the 15th century onwards, European expansion exported it to all parts of the world. Colonial powers such as Spain, Portugal, England, France, and Belgium often combined territorial expansion with conversion. Missionaries established schools and medical services, translated scriptures, and in some areas used coercive taxation and legal systems to suppress indigenous religions. In modern times, Christianity has become the dominant faith on many continents around the world.
From 2010 to 2020, the number of Christians increased by 6%, from 2.1 billion to 2.3 billion, and remains the largest religion in the world.
Such a lengthy expansion explains its contemporary scale. Between 2010 and 2020, the number of Christians still increased by 122 million, from 2.1 billion to 2.3 billion, an increase of 6%. But the global population is growing faster, with non-Christians growing by 15%, causing the share of Christianity to drop from 31% to 28.8%, with all Christians being lumped into one category, including Catholics, Orthodox, and Protestant denominations such as Baptists, Lutherans, Anglicans, Methodists and Pentecostals.
Geographic shifts: Africa rises, Europe falls
The most striking changes of this decade were geographical rather than numerical. Europe, the historical center of Christianity, no longer has the largest Christian population. The number of Christians declined in both regions. In Europe, the number of Christians fell to 505 million (down 9%). In North America, this number decreased to 238 million (down 11%). In every other region, the number of Christians is growing. Sub-Saharan Africa saw the largest increase, reaching 697 million (+31%).
- Sub-Saharan Africa: 697 million Christians (up 31%)
- Europe: 505 million (down 9%)
- North America: 238 million (down 11%)
As of 2020, 31% of Christians live in sub-Saharan Africa, compared with 22% in Europe. Latin America and the Caribbean account for 24% of the world’s Christians, and North America 10%.
Between 2010 and 2020, the number of Christian believers in sub-Saharan Africa increased by 31%, reaching 697 million believers.
The proportion of the population identifying as Christian has also changed:
- North America: 63% (down 14 percentage points)
- Europe: 67% (down 8 percentage points)
- Latin America and the Caribbean: 85% (down 5 percentage points)
- Sub-Saharan Africa: 62% (up slightly, less than 1 percentage point)
In the Asia-Pacific and Middle East-North Africa regions, Christians still account for less than 10% of the population, down by less than one percentage point.
As of 2020, there are approximately 238 million Christians in North America, accounting for approximately 10% of the world’s total Christian population.
However, when measured by individual countries rather than regions, the United States still has the largest Christian population of any country. As of 2020, about 64% of Americans consider themselves Christians, accounting for about one-tenth of the world’s Christians.Also read: Is religion in decline? As Christianity declines, a quarter of the world’s people are now irreligious, making it the third largest group
Where Christianity declined and where it grew
Significant changes (defined as shifts of at least 5 percentage points) occurred in 41 countries, more than for any other religion. Christianity declined in all but one country. Maximum drop:
- Australia: down 20 points
- Chile: down 18 points
- Uruguay: down 16 points
- United States: down 14 points
- Canada: down 14 points
- Benin: down 5 points
Between 2010 and 2020, the share of Christians in North America fell by 14 percentage points, while in Europe it fell by 8 percentage points.
In some countries, Christianity has lost its majority status:
- UK: 49%
- Australia: 47%
- France: 46%
- Uruguay: 44%
In each case, the religiously unaffiliated made up 40 percent or more of the population. Mozambique was the only country to see a significant increase, rising by 5 percentage points to 61% following the end of the anti-religious government movement in the 1980s. Overall, Christians remain a majority in 120 countries and territories, down from 124 in 2010.
Mechanism: Give up religious belief
The central driver of change was not just birth rates but religious conversion. Christians experienced the greatest net losses: For every 1 person who joins Christianity, 3.1 people leave Christianity. Most people do not join other religions; they become irreligious. This movement explains the declining share of Christianity and the simultaneous growth of “nonbelievers.” Globally, religious conversion shows a clear direction: more people are leaving religions than converting. Among adults aged 18 to 54, for every one person who joins a religion, 3.2 abandon it. Fertility remains important, with Christian birth rates relatively high, but the conversion offsets this. In contrast, Muslim population growth is driven primarily by a younger age structure and higher fertility rates, rather than conversion.
The changing religious landscape
By 2020:
- Christian: 28.8% (2.3 billion)
- Muslim: 25.6%
- No religious affiliation: 24.2%
- Hindus: 14.9%
- Buddhist: 4.1%
Globally, 75.8% of people have a religious affiliation and 24.2% have no religious affiliation.
Currently, independents make up 24.2% of the global population, largely due to the Christian schism.
Figures show Christianity remains the world’s largest religion, but is increasingly concentrated in the Global South and increasingly affected by Western divisions. Over the past century, it has spread across every continent. Over the past decade, its center has quietly shifted.
