I can't give a thorough summary, but I can sketch out two different reasons: mass conversion wasn't really a possibility, and from an early point in history, black-majority churches were part of the "Black Church" and most African-Americans worshipped in Black-led churches in Black-led denominations.

First, mass conversion is a remarkably rare event. Some day in the distant, distant future, I want to write a book about mass social conversion (the conversion of the Roman Empire to Christianity, the conversion of Middle East to Islam after the Arab conquests, the conversion of parts of South Asia to Islam, the Protestant Reformation, etc) so I've tried to look into it as much as possible. It's rare. Doing something like abandoning Christianity en masse would be unprecedented.

Further more, religious change is slow. It took Christians about 300 years (until Constantine) to reach about 10% in the Roman Empire, and another hundred or say years, even after official toleration/support starting with Constantine, for it to become the unambiguous religion of the state (see Rodney Stark's Rise of Christianity). Even after the initial Arab Conquests, it took states about a century to majority Muslim and another century to be almost all Muslim (see Richard Bulliet's Conversion to Islam in the Medieval Period). We're talking about similar time scales, if not longer, for mass conversion to Islam in South Asian (see Richard M. Eaton's work). Religions not rooted in the Near Eastern Monotheistic tradition don't do conversion quite the same, but we're talking longer time scales for Japan and China's adaption of Buddhism, for example. And in all those cases, the old religion was being replaced by one specifically supported by the state and elites--it's hard to get past about 10-20% without some sort of elite support. Even today, people who are unaffiliated are a small minority in the United States--in the 19th century, belonging to a religious community was general more important. Simply disaffiliating with Christianity wasn't a real option until much later, and until Islam began to rise in the Black community in the 1950's and 1960's, there wasn't a real competitor. And, again, the mere existence of a competitor isn't enough to convert the majority--such mass conversions almost always have elite support, and follow the Reform era dictum cuius regio, euius religio (he who rules, his religion--which is to say, the religion of the masses follows the religion of the leaders. This was a diplomatic compromise during the European Wars of religion, but it is also a decent rule of thumb predicting conversions).

But, much much more importantly, the Black Church did tremendous work for the black community (unfortunately, I know less about this since I haven't looked at this since I was an undergraduate about a decade ago). Sure, White slave holders used the Christian religion to justify their race based slavery (the curse of Ham; the institutionalization of slavery in the Hebrew Bible and its lack of condemnation in the Christian New Testament), but it was also the basis of abolitionism. Indeed, the earliest abolitions were almost all religiously inspired (generally non-conformists, especially Quakers). The Exodus story, in particular, provided strong inspiration for escaping slaves and abolitions. If I write the words Way down in Egypt Land... let my people go, many of you probably can hear those words sung in your head as it's a very famous spiritual, one of the many inspired by the Exodus story. Slave rebellions were often also religiously inspired, most famously Nat Turner's. So while Christianity was used as a base for the slave system, it was also used as a base of both black and white anti-slavery. This is, believe it or not, quite a common thing in religious history (political scientists Daniel Philpott has a great article with a title something like "The Political Ambivalence of Religion" which goes into this).

But it's important not to see "the Black Church" as a white-controlled institution, even under slavery. I'm told that Raboteau's Slave Religion: the 'Invisible Institution' in the Antebellum South is someone dated now (it was originally published 35 years ago, in 1978), but it remains a path-breaking touchstone in the literature and a common starting place. This notion of the (locally organized) Black Church during slavery as the invisible Black institution remains an important one--Raboteau book has been cited over 1,100 times, which means it's an incredible blockbuster by the standards of academic history. Church meetings, in many places conducting independently of the slave-owners or at least occasionally independently of them, were one of the few excuses for large groups of slaves to gather without observation.

After the Civil War, the Black Church was generally organized on a national level separate from White denominations. I don't have exact numbers about what proportion of African Americans were part of majority black congregations (almost certainly most for the entire period of 1865-present) or what proportion were part of churches affiliated with Black majority denominations (I don't have exact numbers, but I get the sense it's a majority by the start of the 20th century). Learning all the American Protestant denominations is difficult, but one quickly realizes that there are often parallel white and black organizations. For example, the Southern Baptists are historical white (both Baptists and Methodists split into Southern and Northern branches during the civil war, but Methodists later reunited) but National Baptists (founded 1880) are to this day basically black. Martin Luther King, Jr., for example, was a National Baptist until 1961 when, because of the older leadership's reluctance to take a leading role in the Civil Rights Movement, when he and likeminded people split to form the Progressive National Baptist Convention, which in most ways was the same as the National Baptist Convention, but more active in Civil Rights work. Al Sharpton was another Baptist, and while I'm not sure which national "convention" he was initially affiliated with, I'd be surprised if it wasn't either the National Baptist Convention or a direct split off the National Baptist Convention (the Progressive National Baptist Convention, etc). Jesse Jackson is also Baptist and I would guess had similar affiliations.

The National Baptists are the largest single denomination of the Black Church, but they're not the only one. For example, while Methodists were less segregated than Baptists, there are still Methodist splits into historically African-American denominations: the three of the largest that come to mind are the African Methodist Episcopal Church, the African Methodist Episcopal Church Zion (surprisingly, not a split off the AME Church), and the Christian Methodist Episcopal Church. The first two were founded in the North before the Civil War, the CME Church was a split from Methodist Episcopal Church, South (this was the pro-Confederate half of the antebellum Methodist church that in the 20th century reunited with several other splits into the current United Methodist Church). This separate CME Church was created with the support of White Southern Methodists, who thought it was appropriate for Blacks to have their own religious organization. These racial denominational divides continue even into religious innovations in the 20th century. Pentecostalism Churches really don't emerge until the 1907 (mixed race) Azusa Street Revival (though the closely related Holiness Church movement predates it and anticipates it). The largest Pentecostal denomination currently is the Church of God in Christ (COGIC), which is a historically and predominantly Black denomination, founded as part of the holiness movement but adopting the tenants of Pentecostalism soon afterwards. It's mistaken to think of the church as something imposed on the Black community, but rather, the Church presented one of the first (and for periods, perhaps only) opportunities for the African American community to organize itself, both locally and nationally. Besides Black newspapers and the (elite and initially mixed race) NAACP, the first black-led organization that comes to mind is the Pullman porter union ("the Brotherhood of Sleeping Car Porters), first admitted to the AFL in 1925. It's really hard to underestimate the power and importance of the Black Church in Black America for much of the 19th and 20th centuries.

So in short, we wouldn't expect a mass conversion away from Christianity because there was no real alternative, no real option to be disaffiliated, and no real push from above to change religions. More importantly, though, while Christianity was important to the slave-based racial order in the South, it was also crucial to all Black struggles for rights, really until the late 20th century/early 21st century. Both the anti-Slavery movement and the Civil Rights movements were disproportionately led by religiously motivated leaders. More importantly, from very early points, the Black Church was one of the institutions in America that was run autonomously by African-Americans free from White intervention.

Related question, by the time slavery ended, to what extent were American blacks even aware of alternative religious beliefs like traditional African mythology or Islam? I remember asking here a while ago about Muslims being brought to America through the slave trade--is there any evidence that there were practicing Muslims among the slaves by the end of the civil war?

Hello, friends,

This question has attracted responses that draw on the following sources:

• 21st century interpretations of the Bible
• 18th century white pro-slavery preachers
• incorrect interpretations of 20th century sociologists
• 19th century European philosophers

No one has yet to address the actual question from the perspective of Christian slaves, emancipated people, and/or their descendants.

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