Christianity in the United States
Based on Wikipedia: Christianity in the United States
The Largest Christian Nation on Earth
Here's a number that might surprise you: 235 million. That's how many Christians live in the United States, making it the largest Christian nation on the planet by raw population. Not by percentage—Brazil, Mexico, and several other countries have higher proportions of Christians—but by sheer numbers, America stands alone.
What makes this particularly interesting is how that massive number breaks down. It's not one monolithic block. American Christianity is a patchwork of hundreds of denominations, theological traditions, and cultural expressions that have been shaped by four centuries of immigration, revival movements, theological disputes, and social change.
The Big Three Categories
If you want to understand American Christianity, you need to understand three main categories: Evangelical Protestants, Mainline Protestants, and Catholics. These aren't just theological distinctions—they represent different cultures, different voting patterns, different educational backgrounds, and often different neighborhoods.
Protestants of all types make up about 45 percent of the American population, with Catholics coming in second at around 22 percent. But that Protestant number hides an enormous diversity. The Southern Baptist Convention alone has more members than most countries have citizens. Meanwhile, tiny Quaker meetings might have only a dozen people gathering on Sunday mornings.
Then there are the smaller groups that don't fit neatly into these categories: Eastern Orthodox Christians, members of the Church of Jesus Christ of Latter-day Saints (often called Mormons), Jehovah's Witnesses, and various other traditions. Together they represent only about 2 to 3 percent of the population, but they add important threads to the American religious tapestry.
The Evangelical and Mainline Divide
Perhaps no distinction in American Christianity causes more confusion than the difference between Evangelical and Mainline Protestants. The words themselves don't help—"evangelical" comes from a Greek word meaning "good news," which all Christians claim to believe in, and "mainline" sounds like it should mean the largest or most common, which it doesn't anymore.
Here's the key difference: it's about how you read the Bible and how you engage with modern culture.
Evangelicals emphasize what theologian David Bebbington identified as four core priorities. First, conversionism—the belief that people need a personal, conscious decision to accept Jesus, often called being "born again." Second, activism—a drive to share this message with others. Third, biblicism—treating the Bible as the ultimate authority for faith and practice. Fourth, crucicentrism—focusing on Jesus's death on the cross as the central event of human history.
Mainline Protestants, by contrast, tend to read the Bible as a document that requires interpretation through the lens of historical context, literary analysis, and ongoing theological reflection. They're generally more comfortable with ambiguity, more open to changing positions on social issues, and more likely to emphasize Christianity's call to social justice over personal conversion.
But here's where it gets complicated: these categories are blurring. Some Evangelical churches now support women's ordination, while some Mainline congregations hold quite traditional views on social issues. The "Emergent Church" movement of the early 2000s deliberately tried to transcend these categories entirely, taking spiritual practices from both traditions while questioning the assumptions of each.
A Fundamentalist Footnote
You might be wondering where Fundamentalists fit in. Aren't they just really conservative Evangelicals?
Not exactly. Fundamentalism emerged in the early twentieth century as a reaction against what its founders saw as dangerous modernist ideas creeping into Protestant churches—things like Darwin's theory of evolution, historical criticism of the Bible, and liberal theology that questioned traditional doctrines.
Evangelicalism, as a movement, actually began as a breakaway from Fundamentalism. In the 1940s and 1950s, leaders like Billy Graham argued that Fundamentalists had become too separatist, too combative, and too dismissive of intellectual engagement with the wider culture. Evangelicals wanted to reassert orthodox Christian beliefs while remaining engaged with society.
So Evangelicalism occupies a kind of middle ground—more theologically conservative than Mainline Protestantism, but more culturally engaged than Fundamentalism. Think of it as a spectrum: Mainline on one end, Fundamentalist on the other, with Evangelical somewhere in between, though closer to the Fundamentalist side on matters of doctrine.
The Heritage Churches
The Mainline Protestant denominations tell the story of American immigration in their very names.
The Episcopal Church descends from the Church of England, brought over by English colonists. After the American Revolution, it obviously couldn't remain officially part of the English church, so it reorganized under a new name—"Episcopal" simply refers to its structure of governance by bishops.
Presbyterian churches came largely from Scottish immigrants, bringing with them John Knox's Reformed theology and a system of governance by elders (the word "presbyter" means elder in Greek).
Methodists arrived from England and Wales, followers of John Wesley's emphasis on personal holiness and methodical spiritual practices—hence the somewhat mocking name that stuck.
Lutherans came primarily from German and Scandinavian immigration, bringing Martin Luther's theology from the Reformation's original heartland.
This heritage explains something curious about Mainline Protestantism: its members tend to be wealthier and better educated than other religious groups in America. Families like the Vanderbilts, Rockefellers, Roosevelts, and Morgans were Mainline Protestants. These weren't just churchgoers—they founded many of America's most prestigious universities, including Harvard, Yale, Princeton, Columbia, and Dartmouth, all of which began as Mainline Protestant institutions (though most have long since become secular).
Between 1901 and 1972, a striking 72 percent of American Nobel Prize winners came from Protestant backgrounds. In chemistry specifically, that number rose to 84 percent.
The Seven Sisters
Historian William Hutchison coined a memorable phrase for the seven largest Mainline Protestant denominations during the early and mid-twentieth century: the "Seven Sisters of American Protestantism." Like the Seven Sisters colleges, the name suggests both prestige and a certain cultural homogeneity.
The United Methodist Church remains the largest, with about 4.2 million members as of 2023—though this represents a significant decline from its mid-twentieth century peak. The Evangelical Lutheran Church in America follows with roughly 2.8 million members. Then come the Episcopalians, American Baptists, Presbyterians (the denomination known as Presbyterian Church USA, not to be confused with more conservative Presbyterian bodies), the United Church of Christ, and the Christian Church (Disciples of Christ).
These numbers have been falling for decades. The shift is partly demographic—Mainline Protestants tend to have smaller families than Evangelicals or Catholics—and partly theological. Many observers argue that Mainline churches' openness to contemporary ideas has made them less distinctive, less demanding, and ultimately less compelling to potential members.
Where are those members going? Some have joined Evangelical churches. Many have simply stopped attending church at all. The rise of Americans who identify as religiously unaffiliated—the so-called "nones"—has drawn heavily from people raised in Mainline Protestant homes.
Baptists: America's Homegrown Tradition
Baptists deserve special attention because they're America's largest Protestant family and because they defy easy categorization.
The Southern Baptist Convention is the single largest Protestant denomination in America—larger than any Mainline church, larger than any other Evangelical body. It began in 1845 when Baptists in the South split from their Northern counterparts over the issue of slavery. Southern Baptists at the time defended the institution, a position the denomination formally apologized for in 1995.
Today, the Southern Baptist Convention is firmly Evangelical in theology and generally conservative in politics. But there are also Baptist churches that belong to Mainline organizations, like the American Baptist Churches USA. And there are historically Black Baptist denominations, like the National Baptist Convention, which have their own distinct history and culture shaped by the experience of slavery, segregation, and the Civil Rights movement.
What unites all Baptists is believer's baptism—the practice of baptizing only those who have made a conscious profession of faith, rather than baptizing infants. This might seem like a minor detail, but it represents a fundamentally different understanding of how people become Christians. For Baptists, faith must be chosen, not inherited.
The Catholic Story
Catholicism in America has a complicated history. In the early days of the Republic, Catholics were a tiny minority, concentrated mainly in Maryland—a colony founded in 1634 specifically as a refuge for English Catholics fleeing persecution.
But America kept getting bigger.
The Louisiana Purchase in 1803 added vast territories that had been colonized by Catholic France and Spain. Florida, acquired in 1819, had been Spanish Catholic territory since the sixteenth century. The Mexican-American War of 1846-1848 added California and the Southwest, regions with centuries of Catholic mission history. St. Augustine, Florida, holds the distinction of being home to the first Catholic parish in what's now the continental United States, established in 1565—55 years before the Pilgrims landed at Plymouth Rock.
Then came the great immigration waves. Irish Catholics fleeing the potato famine. Italian Catholics seeking economic opportunity. Polish, Czech, and other Eastern European Catholics. Hispanic Catholics from Mexico, Central America, and the Caribbean. Filipino Catholics from America's former Pacific colony.
Today, the Catholic Church has about 67 million members in the United States, making it the largest single Christian denomination—though not the largest tradition, since all Protestant denominations combined still outnumber Catholics. America has the fourth-largest Catholic population in the world, behind only Brazil, Mexico, and the Philippines.
The Eastern Christians
When most Americans think of Christianity, they think of the Western varieties—Protestant and Catholic. But Christianity split long before the Reformation. In 1054, a theological and political dispute divided Christianity into Western (Catholic) and Eastern (Orthodox) branches. Earlier still, in the fifth century, disputes over how to describe Jesus's divine and human natures led several churches to go their separate ways—these are today called Oriental Orthodox churches (not to be confused with Eastern Orthodox).
Both Eastern Orthodox and Oriental Orthodox Christians have communities in America, though together they make up less than one percent of the population. Greek Orthodox churches came with Greek immigrants. Russian Orthodox churches have a fascinating history—Russian missionaries actually established Orthodox Christianity in Alaska when it was still Russian territory, before the United States purchased it in 1867. Serbian, Romanian, Ukrainian, Antiochian, and other Orthodox communities established churches as their immigrant populations grew.
The Oriental Orthodox churches include the Coptic Orthodox (Egyptian), Ethiopian Orthodox, Armenian Apostolic, and several others. These ancient churches trace their origins to the earliest centuries of Christianity and maintain traditions that predate the East-West split of 1054.
There's also a curious outlier: the Mar Thoma Syrian Church, which traces its origins to Saint Thomas the Apostle's legendary mission to India in the first century. This church combined ancient Eastern Christian practices with Protestant theology introduced by Anglican missionaries in the nineteenth century, creating a unique synthesis. It maintains full communion with the Anglican Communion, bridging East and West in an unusual way.
The Numbers Game
Every survey of American religion produces slightly different numbers, which can be frustrating if you're looking for precision. But the trends are clear and consistent across all the major studies.
American Christianity is shrinking as a percentage of the population. In 1990, about 85 percent of Americans identified as Christian. By 2001, that had dropped to about 82 percent. By 2015, it was 75 percent. The most recent surveys put it somewhere between 65 and 70 percent.
Where are those people going? Mostly to no religion at all. The "nones"—people who identify as atheist, agnostic, or "nothing in particular"—have grown from about 8 percent of the population in 1990 to roughly 30 percent today. This is the most dramatic shift in American religious history.
But wait—235 million Christians is still an enormous number. How can Christianity be both declining and still so dominant?
It's a matter of percentages versus absolute numbers. The American population has grown substantially since 1990. Even as Christianity's share of the population has dropped, the raw number of Christians has remained relatively stable. Meanwhile, the religiously unaffiliated have gone from a small minority to nearly a third of the country.
The Non-Denominational Phenomenon
One of the most significant developments in recent American Christianity has happened almost invisibly in the data: the rise of non-denominational churches.
These are churches that don't belong to any of the traditional denominational structures. They don't answer to a bishop or a denominational headquarters. They're independent congregations, often founded by a charismatic pastor, that identify simply as "Christian" or "Bible church" or give themselves creative names that don't signal any denominational heritage.
By 2020, non-denominational Christians had become the second-largest Christian group in America, overtaking Baptists. They now make up more than 13 percent of religiously affiliated Americans and about 6.4 percent of the general population.
What's driving this growth? Partly it's a rejection of institutional religion—people want to be Christian without all the denominational baggage. Partly it's entrepreneurial—non-denominational churches can adapt quickly to local needs without seeking permission from distant headquarters. And partly it's theological—many non-denominational churches are Evangelical in their beliefs but don't want to be tied to the political and cultural associations that come with denominational labels.
Christianity and Immigration
America's Christian population continues to be shaped by immigration in fascinating ways. Among Korean Americans, an astonishing 71 percent identify as Christian—far higher than the rate in South Korea itself. Christianity became intertwined with Korean American identity partly because churches served as community centers for immigrants navigating a new culture.
Chinese Americans are about 30 percent Christian, and Japanese Americans about 37 percent. In both cases, these percentages are much higher than in the ancestral homeland, suggesting that something about the American experience encourages conversion to Christianity.
Hispanic immigration has transformed American Catholicism, bringing new energy and sometimes new tensions to a church that was historically dominated by Irish, Italian, and Polish ethnic cultures. Many Hispanic Catholics practice a form of the faith that blends Catholic doctrine with indigenous traditions in ways that can seem foreign to European-descended Catholics.
Meanwhile, immigrants from traditionally Muslim countries have contributed to a small but growing population of Christians from Muslim backgrounds—an estimated 450,000 people, many of whom converted after arriving in America. Most join Evangelical or Pentecostal churches.
What Does It All Mean?
The story of Christianity in America is ultimately a story about pluralism and fragmentation. There is no single "American Christianity"—there are hundreds of variations, from tiny Amish communities in Pennsylvania to megachurches in Texas with their own coffee shops and bookstores, from ancient Orthodox liturgies conducted in Greek to contemporary worship services with rock bands and laser light shows.
This diversity is both a strength and a weakness. It means that almost anyone can find a Christian community that fits their preferences. But it also means that Christians often struggle to speak with a unified voice on social and political issues. What does "the Christian position" on immigration or healthcare or economics look like when Christians themselves disagree so profoundly?
The decline in Christian identification raises its own questions. Is this a temporary dip or a permanent shift? Will America eventually look more like secular Western Europe, where active Christian practice has become a minority phenomenon? Or will Christianity adapt and find new forms of expression that resonate with future generations?
The only certainty is that the story isn't over. American Christianity has reinvented itself many times—through the Great Awakenings of the eighteenth and nineteenth centuries, through the fundamentalist-modernist controversy of the early twentieth century, through the Civil Rights movement, through the rise of the Religious Right. Whatever comes next, it will likely surprise everyone who tries to predict it.