Benjamin L. Miller's In God's Presence: Chaplains, Missionaries, and Religious Space during the American Civil War examines how clergy and soldiers adapted and developed religious practices during the disruption of war. Central to the book is Miller's concept of religious space, a place “where one confers with the divine” (2). Clergy and troops, he contends, created special spaces for religious activities. The new spaces differed from religious spaces in antebellum America, particularly because they lacked women and children and were more ecumenical and democratic. These differences, he argues, transformed the soldiers’ experiences of religion, changes that shaped the postbellum religious landscape of the United States. Miller brings a host of experiences to bear on his subject matter, particularly the writings of chaplains of various denominations as well as the activities of the United States Christian Commission, a northern evangelical organization that provided support for the religious needs of Union soldiers. (12–22) Miller's concept of religious spaces, however, weakens the book.

Miller uses the category of religious space as a comprehensive model that could allow him to generalize and escape the thicket of denominational histories. Following the logic of his model, Miller notes that before 1861 American religious groups had created separate spaces along denominational lines in individual church buildings. Clergy presided over the interior sacred spaces, while the profane world sprawled outside church doors. During wartime, however, clergy and soldiers normally lacked separate permanent worship spaces. Although Miller notes that groups did build temporary chapels if the armies remained stationary for some time, the antebellum separation of sacred and profane space did not exist in such a neat fashion in “military camps, battlefields, hospitals, and prisons[,]” the venues for wartime religious labors (70–73, 147). Instead, men of all different religious denominations contended to carve out separate and usually temporary religious spaces for use. Often, different denominations, Miller argues, shared the same space. Thus, all denominations, lacking separate religious retreats, faced the profane world together and shared concerns about the ubiquitous irreligious behavior of both churched and unchurched troops, particularly gambling, swearing, and intemperance (75–85). Shared religious spaces and shared concerns about profane conduct produced a democratic equality among Christian troops and an ecumenism that melted away denominational differences (2, 5, 39, 150). Many clergy had to minister to people they would not normally have encountered in their antebellum religious domains, specifically blacks and immigrants. (86, 129) Tending to wounded and dying men on the battlefield and the hospitals required clergy to stretch antebellum religious boundaries and practices as well (94–123). Instead of treating missionaries and chaplains primarily along denominational or doctrinal lines, Miller sees them as performing a common task of creating religious spaces in the ever-shifting landscape of the war.

Miller's conceptual framework is intriguing and suggestive, but his model is often ahistorical and his evidence does not always support his claims. The example of ecumenism is most instructive. Interdenominational cooperation, especially among Protestants, was not uncommon in antebellum America, especially on the frontier where denominations sometimes shared buildings. In addition, scholars have often noted about the Second Great Awakening that support for revivalism crossed denominational lines and often led to interdenominational cooperation. Other scholars have long stressed that nineteenth-century anti-Catholicism intentionally served as a way to increase Protestant unity against perceived cultural and religious threats. Miller's model misses this context. He posits, instead, ecumenism as a development of the War, writing, “Soldiers and clergy largely abandoned denominational and sectarian differences that had been important before the war” (5). While providing several examples, he notes numerous exceptions. On page fifty-two, Miller tells of Baptist soldiers refusing to attend an Episcopal communion service. A few pages later he relates the failed attempt of a Catholic chaplain to convert a soldier due to the man's status as a Freemason, which Catholicism condemned (58). Miller even notes that “clergy in the field seemed to mirror the attitudes of their home denominations” (56). It seems, therefore, that while ecumenism is a logical expectation flowing from Miller's model of religious space, his evidence challenges these expectations. Similarly, his claims for the transformative influence of the Civil War on American religion remain suggestive. Ecumenism as well as the democratic equality of camp religion, he admits, quickly crumbed after 1865 (150). Wartime exigencies, as students of war recognize, often create temporary solutions that are abandoned once the moment passes. Postbellum America certainly, as Miller asserts, “contained vestiges of the chaos of the wartime spiritual world” (155). He needed, however, more evidence to establish firmly that point.

In God's Presence is a mixed bag. Miller's extensive archival research uncovered a number of interesting figures and examples of wartime religion. But his model oversimplifies nineteenth-century religion in America.