The US Civil War has long attracted the notice of many historians. It is also still one of the most politically volatile topics. This is due in part to the prevalence of the concept of the “Lost Cause.” The name comes from the book The Lost Cause: A New Southern History of the War of the Confederates, written by the journalist Edward Pollard and published in 1866.

Pollard established many of the common claims repeated by Lost Cause writers. These claims include that the horrors of enslavement were exaggerated and that enslavement as an institution would have died out anyway; that the Civil War was actually fought over the political issue of states’ rights; that the Union was the true aggressor; and that the sole reason the Confederacy lost was because of the superior economic power of the North. These claims are rejected by mainstream historians and were contested from the beginning. Nevertheless, the Lost Cause has been bolstered by the writings of former Confederates like Jefferson Davis and by later scholars and political activists.

The historical work of Charles A. and Mary Beard in the early 20th century seemed to support the Lost Cause thesis, at least to an extent. Their work and the historical consensus for much of the first half of the 20th century downplayed the role of enslavement and the debates over free and pro-enslavement states. They instead emphasized economic causes of the Civil War, such as the South’s economy remaining agricultural while the North industrialized, as well as conflicts over tariff and banking policies. Some other historians at the time denied that there were significant political, institutional, and social divisions between the South and the North, instead attributing the war to the influence of abolitionists in the North and fire-eaters (a group of pro-secessionist Democrats) in the South.

Battle Cry of Freedom fits into more recent developments in Civil War historiography since the 1960s that were informed by the Civil Rights movement. These approaches do not jettison the idea that there were economic elements in the causes of the Civil War, but argue that these causes were nonetheless often rooted in enslavement. They also examine how enslavement shaped the social, political, and cultural institutions of the South. In Battle Cry of Freedom, for instance, McPherson argues that the massive expansion of the United States’ territory following the Mexican-American War led up to the Civil War, but the underlying controversy affecting myriad developments was enslavement.

Further, this historiography also presents racism and the concept of white supremacy as powerful cultural factors that also contributed to the Civil War breaking out, shaping public attitudes during the war in both the South and the North. These are generally the views presented in popular accounts of the Civil War, most famously Ken Burns’s 1990 The Civil War documentary series. While the Lost Cause interpretation has been thoroughly discredited to the point that it is often referred to as a myth or pseudohistory, passionate disagreements over how the Civil War is treated by professional historians and in memorials and works of popular history still break down along political, ideological, and even regional lines.