The Civil War was a major turning point in American religious thought, argues Mark A. Noll. Although Christian believers agreed with one another that the Bible was authoritative and that it should be interpreted through commonsense principles, there was rampant disagreement about what Scripture taught about slavery. Furthermore, most Americans continued to believe that God ruled over the affairs of people and nations, but they were radically divided in their interpretations of what God was doing in and through the war.

In addition to examining what white and black Americans wrote about slavery and race, Noll surveys commentary from foreign observers. Protestants and Catholics in Europe and Canada saw clearly that no matter how much the voluntary reliance on scriptural authority had contributed to the construction of national civilization, if there were no higher religious authority than personal interpretation regarding an issue as contentious as slavery, the resulting public deadlock would amount to a full-blown theological crisis. By highlighting this theological conflict, Noll adds to our understanding of not only the origins but also the intensity of the Civil War.