This massive work is the result of four decades of comparative study of the titular plantations, Mesopotamia in western Jamaica, and Mount Airy in Tidewater, Virginia. Having begun in the era of the punch card and concluded in that of the Internet, Dunn's monograph centres on each estate's exceptionally detailed sets of slave records, documents which made it possible for him both to trace the individual life trajectories of hundreds of enslaved men and women over several generations and to draw broader conclusions about the ways in which the practice of slavery varied between the West Indies and the American South from the mid-eighteenth century to the Civil War, a period which saw the ending of slavery in the former location and its dramatic expansion and sudden destruction in the latter. The result is a career-capping work of historical enquiry which offers a model for further scholarship in the social history of slavery throughout the Anglo-Atlantic world, and indeed beyond it.

In relation to the demography of the enslaved populations of Mesopotamia and Mount Airy, Dunn's meticulous and carefully explained analysis produces an inescapable conclusion which provides archival support for historiographical truisms regarding the divergence of population trends between Caribbean and North American slave plantations. While the Mesopotamia slaves had in the estate's 1727 and 1736 inventories been “youthful and vigorous,” a generation later, in 1762, they were “strikingly elderly” (34) on both the individual and the communal level, a situation which had dire ramifications for their potential in both productive and reproductive labour. In the 1780s, as the Jamaican economy recovered from the effects of the American Revolution and adjusted itself to the postwar status quo, the estate's owners, the Barham family, purchased sixty-five new slaves from Africa, with whom they hoped to rejuvenate their enslaved population, but this addition, followed by others over the next four decades, failed in this goal. In Dunn's view, this ongoing demographic failure, the result of low fertility and high mortality, shows “an extraordinarily abusive slave system at work” (43), one which mired the enslaved in misery without generating significant profits for their owners. In striking contrast, at the Tayloe family's Mount Airy, the “constant growth of this slave population was a tremendously powerful engine” (61) of economic success; with high rates of fertility and low levels of mortality amongst their slaves, the Tayloes owned so many healthy male and female labourers that they could not only fully staff the home plantation but send many bondspeople away to the family's new cotton farms in Alabama, in which endeavour they were part of the immense relocation of slave labour from the Upper to the Lower South, which Edward Baptist has recently detailed in The Half Has Never Been Told (2014).

One might assume from the book's early focus on demography that its interpretation of the development of slavery might mirror that of Fogel and Engerman's Time on the Cross (1974), a seminal work that appeared at the time at which Dunn began this project, and one widely criticized for its treatment of its subjects as units of data rather than as human beings. But Dunn has mined his materials in a way which allows him to see individual members of the Mount Airy and Mesopotamia communities as the subjects of their own stories, rather than as “disposable cogs in a machine” in Jamaica or as “locked into a multistate system” (73) in the United States. A pair of chapters trace the family histories of two women, Mesopotamia's Sarah Affir and Mount Airy's Winney Grimshaw, illuminating the familial and emotional landscapes of illiterate women in a way that is so rarely possible for historians of slavery. Readers are able to learn more not only about Affir and Grimshaw's families but also about those of other members of the two plantation communities at this book's companion website, “Two Plantations,” hosted by Harvard University's History Design Studio (www.twoplantations.com), in which Dunn and his technical team have been able to present and analyse material which could not be included in the monograph.

Over the past few years, scholars such as Simon Newman and Justin Roberts have emphasized the “how” as well as the “why” of slavery and plantation management in the West Indies and the American South, drawing upon exceptionally detailed sets of estate records in order to reconstruct the day-to-day routines of plantation life and the agency of the enslaved therein. A Tale of Two Plantations continues this valuable line of enquiry, and will encourage historians to seek out further archival resources and innovative modes of analysis which will continue to refine our understanding of the ways in which lives were made and remade within the world of slavery.