During the past six years or so Sam Haselby has taught history at both the University of Beirut and the University of Cairo. Perhaps the experience of teaching at these two Middle Eastern universities convinced him that religion tends to trump politics every time. For that is a major theme of his impressive and powerfully argued book [The Origins of American Religious Nationalism]—that in the decades following the American Revolution it was American Protestantism and not any sort of classical republicanism that was most important in shaping the development of American nationalism.

The break with Great Britain, says Haselby, who is currently a visiting professor at Columbia, freed Americans from the restraints imposed by British imperial considerations. In the half-century following the Declaration of Independence, tens of thousands of the rapidly growing population of Americans swarmed over the mountains into the trans-Appalachian West (the region west of the Appalachians and east of the Mississippi River). In 1790 the trans-Appalachian population was about a hundred thousand; by 1820 it had swelled to two and a quarter million. By 1821, nine new western states—Kentucky, Tennessee, Indiana, Louisiana, Ohio, Illinois, Alabama, Mississippi, and Missouri—had entered the Union. By 1825, Kentucky and Tennessee alone had more people than Massachusetts, Connecticut, Rhode Island, and Vermont combined. This extraordinary movement of people, Haselby says, “produced a new mode of nationalism, one more enduring than revolutionary-era civic republicanism, and more unruly.”

This western territory became the battleground of a momentous struggle over what kind of country the new United States would become. Would it emerge as a replica of the small, religiously conservative farming communities of New England? Or would it come to resemble the Jeffersonian society of the South, dominated by deistic-minded slaveholding planters? As it turned out neither the religiously conservative society of New England nor the secular Jeffersonian South came to dominate the West. Instead, the West experienced a struggle within Protestantism between what Haselby labels “frontier revivalism and national evangelism.”

By “frontier revivalism” Haselby means the religion of the migrants, mostly small farmers, who became members of the dynamic Protestant sects that dominated the frontier. And by “national evangelism” he means the northeastern elites, mostly gentry and capitalists, who organized the nationalist Protestant missions program that sought to save the West from the barbarism of the revivalists. The religious conflict between these large movements within Protestantism fundamentally shaped America’s sense of itself as a nation. The ultimate resolution of this conflict, Haselby contends, was expressed in the rise of Andrew Jackson.

The post-revolutionary decades in America may have seen the greatest explosion of Christian religiosity since the seventeenth century or even the Reformation. The entire religious landscape of America was transformed. In 1760 the dominant denominations in colonial America had been the Anglicans and the Congregationalists—traditional state churches with Old World connections. By the end of the eighteenth century the dominant denominations had become the Baptists and Methodists—revivalist sects that had no connection with any state whatever. ...