The material in this course has helped to answer this question. First of all, it is certainly true that the vast majority of the English colonists in America were Christians, and indeed quite a few of the colonies (Massachusetts, New Hampshire, Maryland, Connecticut, Rhode Island, New Jersey, South Carolina, Pennsylvania, and Georgia) were founded in whole or in part for religious reasons.1 Some, like Pennsylvania and Rhode Island, were founded as experiments in religious tolerance much like what we experience today. The Massachusetts Bay colony was founded by Puritans wishing to establish a theocracy according to their convictions.2 Still others, like the Plymouth Plantation, were founded by religious dissidents seeking freedom from persecution (though this did not mean they were always tolerant of other churches). Maryland was even founded as a haven for English Catholics.3 Several of the colonies had established churches, either Anglican or Congregationalist.4 So the American colonies displayed a wide range of attitude towards religion, from full tolerance to relative apathy to what could definitely be called a "Christian colony".
The case for a "Christian nation" doesn't do much better if it turns to the founding fathers. Fully two-thirds of them were Anglican5, but most were relatively cool to religion and held faiths strongly influenced by the Enlightenment and Deism. Benjamin Franklin seldom attended church and didn't care to spend energy affirming the divinity of Christ. Thomas Jefferson distrusted organized religion and, famously, created the "Jefferson Bible" by cutting out all the parts of his Bible that he disagreed with. George Washington never received communion and preferred to refer to Providence or destiny rather than God.6 The struggle for independence drew inspiration from the political philosophy of the Enlightenment and came with a "rationalist ideology that spoke of Providence above all as a principle of progress."7 This came hand in hand with distaste for what was seen as outmoded Christian dogma and superstition. It's safe to say that by and large, the majority of the founding fathers esteemed Christianity only insofar as it aligned with the "natural religion" of the philosophers and Deists.
Given the patchwork nature of American Christianity and the founding fathers' preference for private, rational religion that left behind the struggles of orthodoxy of the past, it's easy to see how Pennsylvania and Rhode Island's model of religious tolerance became enshrined in the Constitution. It made no reference to Christianity or its God except the date in 'the Year of Our Lord', which was unprecedented at the time.8 The Federal Government had erected a "wall of separation between church and state" (first referred to by Jefferson in 1802) that consciously rejected the established church model of Europe, and one by one the state churches were dismantled, ending in 1833. Established churches became denominations that were free to operate apart from government aid or opposition, the church model which continues to this day.
So it's difficult to see how American can be called, in any meaningful way, a "Christian nation". The founding fathers were certainly no defenders of the faith, much more interested in the ideals of the Enlightenment and natural religion than in anything particular to Christianity. There was nothing distinctly "Christian" about the founding of the federal state as there was with Plymouth or Massachusetts Bay. Certainly the great majority of its population has been at least nominally Christian for much of its history—but what kind of Christian? By the time of its independence, America was home to Baptists, Methodists, Anglicans, Congregationalists, Presbyterians, Quakers, and Catholics, to name a few.
When I hear appeals to America's supposed status as a "Christian nation", it is in the context of an attempt by the speaker to in some way lay claim to America's religious heritage for his own tradition or agenda. But America's religious history, even on the popular level is far too ambiguous for this kind of talk. If America is in some sense a "Christian nation", it is so in all of the diversity that the Church in America had in 1776 and has grown into today. If I may be allowed to finish with a truly atrocious pun, I think it would be more accurate to refer to America in a way that describes its heritage of religious diversity and tolerance: a "denomi-nation".
- Robert C. Walton, Chronological and Background Charts of Church History (Zondervan: Grand Rapids, 2005), chart 96.
- Justo L. González, The Story of Christianity Volume II: The Reformation to the Present Day (New York: HarperCollins, 2010), 280.
- González, The Story of Christianity, 286.
- Walton, Charts of Church History, chart 96.
- Diarmaid MacCulloch, Christianity: The First Three Thousand Years (London: Penguin Books, 2009), 763.
- MacCulloch, Christianity, 764.
- González, The Story of Christianity, 320.
- MacCulloch, Christianity, 764.