RIVER OF DARK DREAMS: Slavery and Empire in the Cotton Kingdom. By Walter Johnson. Harvard University Press. 560 pages. $35.

Walter Johnson’s “River of Dark Dreams” opens with an actual explosion of the engine of a steamboat on the Mississippi that serves as a metaphor for the explosion into war that slavery, the engine of the Cotton Kingdom’s economy, was ultimately to cause.

Johnson’s purpose with this exhaustively researched examination of the Mississippi River Valley between the Louisiana Purchase of 1803 and the formation of the Confederate States of America in 1861 is not to rehash the familiar arguments about the causes of the Civil War but to cause a historiographical explosion of his own.

Johnson argues that to see the Civil War in strictly binary regional terms — as a war between “the South” (in the agrarian corner) and “the North” (representing industrial capitalism) — requires a kind of after-the-fact anachronism.

In Johnson’s view, the slave-holding states of the United States were just as much a part of global industrial capitalism as the nonslave-holding states.

The Civil War was thus a global conflict pitting two notions of essentially the same political economy against each other: the one based on paid labor, the other rooted in enslaved labor. While convincingly establishing these theoretical claims and the connections among cities such as New Orleans, Memphis, Havana, Liverpool and London, it is a great strength of the book that Johnson never loses the gritty focus on the abject material conditions of the enslaved workforce in the Mississippi Valley.

Johnson frames his book with two ironies. He notes that in the first decade of the 19th century, the banning of the international slave trade just a few years after the Louisiana Purchase led to a massive expansion of slavery, entirely counter to Thomas Jefferson’s dreams of an expanded yeoman republic. Johnson does a great job in showing how land speculation in the new territory fueled this expansion and how, once the massive new territory was settled, the slave-holding states began to forge alliances with political and economic forces worldwide that would allow them to spread their power still further.

In the last decade that comes under scrutiny, the 1850s, Johnson details the other irony, how pro-slavery advocates in the Cotton Kingdom used the rhetoric of freedom in attempting to extend the reach of American slavery, notably by bankrolling filibuster attempts in Cuba and Nicaragua, and by pushing to reopen the trans- Atlantic slave trade.

“River of Dark Dreams” thus concludes by challenging its readers as to whether the pro-slavery lobby’s notion of freedom “bearing the vicious stamp of slavery on its underbelly” might better describe our own world than the soothing assumption that freedom is a “natural and inevitable condition.”

Reviewer Simon Lewis is professor of English at the College of Charleston and associate director of the Carolina Lowcountry and Atlantic World program.