Glaze on Sheehan-Dean, 'The Calculus of Violence: How Americans Fought the Civil War'

Aaron Charles Sheehan-Dean
Robert Glaze

Aaron Charles Sheehan-Dean. The Calculus of Violence: How Americans Fought the Civil War. Cambridge: Harvard University Press, 2018. 480 pp. $35.00 (cloth), ISBN 978-0-674-98422-6.

Reviewed by Robert Glaze (Lincoln Memorial University) Published on H-CivWar (October, 2019) Commissioned by Madeleine Forrest (Randolph-Macon College)

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With its now estimated 750,000 deaths, the Civil War was unquestionably a bloody affair. Conventional scholarly wisdom posits that violence increased in quality and quantity over time as the war transitioned from limited to total and Union occupation policies evolved from soft to hard. It reached its crescendo in the bloody battles of 1864 and Sherman’s subjugation of Georgia and the Carolinas. Reassessing this consensus, Aaron Sheehan-Dean convincingly reveals a more complex and nuanced story. Instead of a simple chronologically linear progression, Sheehan-Dean argues that violence in the Civil War, which he significantly identifies as the product of human agency, varied across time and space. Simply put, what was the bloodiest day of the war for one locale was likely the most peaceful for another. In this masterful exploration of Civil War violence, Sheehan-Dean ultimately concludes that the war was “a catastrophically bloody conflict that could have been much worse” (p. 7). During the bloodiest conflict in American history, warring sides both aimed to wage a “just war.”[1]

Numerous factors such as Christianity, Enlightenment ideology, and respect for a shared past are credited with restraining violence, but the author argues that the Union and Confederate governments were the most important practical tools in limiting bloodshed. Nineteenth-century Americans believed that only states could make war. Both nation-states valued international opinion and respected accepted rules of war. Both practiced conventional warfare, accepted surrenders, and took prisoners. State-initiated restraint played out in numerous ways. For example, despite vocally denouncing the Confederacy’s legitimacy, Lincoln and the Union treated their adversary as a legitimate nation-state, not as a treasonous cabal. Both sides tacitly—and usually practically—recognized the sanctity of noncombatant life. While acknowledging that both polities failed at times to restrain violence, Sheehan-Dean provides the sure-to-be-debated conclusion that “the Civil War reveals that states matter” (p. 3).

While Sheehan-Dean’s thesis emphasizes restraint, he acknowledges that the war did include episodes of unrestrained violence. In that respect, A Calculus of Violence is concerned with explaining both the rule of restraint and the exception of excess. Guerilla warfare proved the most significant catalyst for cruelty. Indeed, the Confederacy’s failure to bring partisans to heel is shown to be one of that state’s failures in containing bloodshed. Guerilla violence, typically occurring at the periphery of state power, led to a violent cycle of attacks and reprisals. Because Union officers considered guerilla warfare a violation of accepted norms, they were less inclined to treat partisans and their supporters with restraint.

Emancipation, which the Confederacy saw as proof of Yankee barbarism, often led to excessive violence. Rebels saw the end of the peculiar institution and the enlistment of black soldiers as tantamount to a slave rebellion. With the fabric of their reality unraveling, white Southerners lashed out in brutality. Confederate massacres of black troops at Fort Pillow and the Battle of the Crater are cited as evidence of racially motivated malice. Nevertheless, while such episodes mark a departure from restraint, Sheehan-Dean explains that they are not evidence of Rebeldom abandoning its desire for a just war. From the Confederate perspective, because emancipation and black enlistment were unjust, they were under no obligation to wage just war against USCT soldiers. In addition to bloodshed on the battlefield, emancipation increased suffering in prisoner-of-war camps. Confederates refused to recognize USCT soldiers as legitimate combatants and thus denied them prisoner-of-war status. Prisoner exchange systems consequently broke down, leading to overcrowding, disease, squalor, and death for captured combatants.

While emancipation proved a catalyst for violence, the emancipated themselves proved a restraining force. Sheehan-Dean credits freedpeople’s decision to pursue liberty instead of revenge as another of the war's moderating influence. “The absence of such emancipation-related violence,” contends the author, “is the single most important factor that limited the bloodshed in the Civil War” (p. 153). Former southern slave owners were spared the cycle of revenge-motivated violence that plagued Haiti in the wake of its successful slave revolt.

Lastly, nationalism proved a double-edged sword. On the one hand, Northerners and Southerners alike valued being members of legitimate, civilized states and they were committed to waging war accordingly. On the other hand, one side’s conviction of its own righteousness and the other’s barbarity could mentally and emotionally justify excessive violence. Nationalistic rhetoric, whether from a preacher, politician, or editor, was a powerful determinant for the war’s participants.

Situating the war in an international context adds further credence to Sheehan-Dean’s conclusions. The 1857 Indian Revolt loomed large in the minds of Civil War Americans as a conflict of depravity and atrocity. Both Northerners and Southerners bristled at comparisons to the Sepoys. Moreover, “the most destructive nineteenth-century wars, like the Caste War of the Yucatan or the Taiping Civil War, involved actors who did not aspire to statehood or who rejected the Western laws of war” (p. 3). Captured soldiers were also routinely executed in these conflicts. While international comparisons in The Calculus of Violence are brief, the author has promised to focus on these comparisons in a forthcoming book.  

Sheehan-Dean’s conclusions are a product of his book’s staggering scope. The battlefield and the home front, conventional and irregular engagements, urban and rural settings, and the experiences of whites and blacks are all shown careful attention. While some of these dualities do not survive the author’s analysis, it is this multitude of perspectives that complicates the presumed linear trajectory of Civil War violence. When comparing conventional pitched battles exclusively, the war clearly became more violent as time progressed. Casualties at Cold Harbor dwarfed those of First Manassas. However, “rather than seeing the rising death toll on the battlefields as driving a more desperate and violent war, we must also recognize that this occurred even as participants committed themselves, in new and earnest ways, to a lawful and just war” (p. 246).

In problematizing long-held assumptions, Sheehan-Dean adds needed complexity to our understanding of how Americans fought their Civil War. Clean binaries and axiomatic paradigms fare poorly in the pages of The Calculus of Violence—an immensely important book that deserves wide readership. Political, military, social, and cultural historians of the Civil War all have much to glean from its pages. But the book’s greatest utility will likely be the dialogue, debate, and further research it inspires within Civil War history. Graduate seminars, conference panels, and roundtables will all profit from this book’s publication.


[1]. The author acknowledges the problematic nature of this term and, eschewing presentism, makes it clear that he is concerned solely with how nineteenth-century Americans conceptualized the notion of a “just war.”

Citation: Robert Glaze. Review of Sheehan-Dean, Aaron Charles, The Calculus of Violence: How Americans Fought the Civil War. H-CivWar, H-Net Reviews. October, 2019. URL:

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