William Patrick O'Brien's Merchants of Independence explores the international commerce that linked western Missouri with Mexico before the U.S. Civil War. Using the town of Independence, Missouri, as the center of his story, O'Brien focuses on the period from the town's founding in 1827 to its demise as an international entrepôt because of the economic disruption and guerilla raiding of the Civil War in western Missouri. By using Independence to ground his depiction of this commerce, O'Brien is able to helpfully focus on the stories of specific key traders, such as Samuel C. Owens, a founder of Independence who died in the Mexican-American War, and Hiram Young, a free black man whose wagon business flourished in Independence in the 1850s. Using biographical and commercial details, O'Brien shows how these and other merchants in Independence were part of “an international economic network” (p. 4), and theirs was not simply a regional story.

O'Brien details the extent and implications of overland trade from western Missouri to Santa Fe, and beyond to Chihuahua. This trade network was especially centered on the export of manufactured cloth and the import of Mexican silver. O'Brien contends that the influx of silver from Mexico helped buffer the economy around Independence “from the national economic problems caused by the depressions in 1837 and 1857” (p. 73). To show the scope of the trade, O'Brien engages the available statistics throughout the text and a table in the third appendix lists the “value of selected shipments entering Missouri from Mexico between 1832 and 1853” (p. 181). O'Brien is particularly interested in on how local traders responded to the diversity inherent in international trade. He argues that the “constant potential for conflict = served as the catalyst that drove people toward consensus” (p. 7). Even if local merchants wanted to be as independent as their town's name, they found they needed to find ways to work with others or else they would not succeed.

O'Brien makes clear, however, that the interactions among these diverse people were not all benign, indeed there was an element of coercion and at times even violence. Merchants in Independence used legal systems, property ownership, and sometimes marriage to try to manage their risks. In addition, O'Brien makes extensive use of the R. G. Dun & Co. Credit Reports to help illustrate the importance of the merchants' “ability to monitor” (p. 9) their allies and competitors through a national credit reporting system. Although the traders in Independence were willing to associate and exchange with a wide range of people, they were less amenable to diversity that they perceived as a nearby economic threat. Mormons began purchasing numerous town lots in Independence in the 1830s and the resulting conflict led to the Mormons' expulsion from Jackson County. O'Brien asserts that this was a chance for local authorities to “eliminate unwanted competition in the international trade with Mexico” (p. 94), though the local economic competition is clearer in his evidence than an international trade aspect.

The strongest chapter in Merchants of Independence focuses on a particular firm that was instrumental in this trade. In the final chapter, O'Brien demonstrates how the “international business” of William McCoy, David Waldo, and Jabez Smith “depended on the collaboration of various groups of people” (p. 146) in the 1840s and 1850s. McCoy, Waldo, and Smith were immersed in a network of reciprocity and exchange that included Manuel Álvarez in Santa Fe and the firm of Peter Harmony and Nephews in New York City. In this way, according to O'Brien, McCoy and his associates realized that “positive interrelationship of diverse people with mutual interests” (p. 168) could lead to profit for all.

Merchants of Independence would have benefitted from stronger editorial support and guidance. There are small mistakes that distract the reader, such as two different years given for merchant Owens' death (pp. 102 and 121). More problematically, there are many repetitions between chapters, which suggests a different structure and organization might have helped O'Brien better showcase his findings. The chronological flow between the chapters can get muddied, leading to issues of continuity and coherence for O'Brien's story. For example, the fourth chapter concludes by detailing the demise of Independence's international standing in the Santa Fe trade in 1860, but then the fifth chapter shifts back in time to the 1830s, which makes the flow confusing for the reader. If O'Brien meant each chapter to explore substantially different themes, this is not abundantly clear in the divisions between them either. This lack of distinctiveness between chapters is reflected in their titles, with, for example, Chapter 3 called “The Trade,” while Chapter 5 is titled “The Trade and Its People.”

Although its organization and presentation could have been clearer, O'Brien's Merchants of Independence draws attention to an important trade that had regional, national, and international importance during the antebellum period. O'Brien's book will be of particular interest to those who study frontier economies in the United States or elsewhere for comparison. In addition, his story is important for a wider audience as well because he shows how frontier economic activities were enmeshed in and could even help shape national and international economic developments.