In this intriguing book, historian Ryan Hall examines the history of the Blackfoot (Niitsitapi) people, who consist of the Siksika, Kainai, and Piikani nations, on the northwestern Great Plains during the tumultuous era of the fur trade. From their “strategically important” homelands between the Saskatchewan and Missouri Rivers, Hall argues, the Blackfoot effectively “shaped the diffusion of new technologies” and “played outsiders against one another” to become one of “the most powerful, prosperous, and geographically expansive” Indigenous groups in North America “from the late eighteenth through the mid-nineteenth centuries” (pp. 4–5). Challenging conventional national narratives of Native declension and dependence, Hall's book joins a growing body of scholarship showcasing the power and resiliency of Indigenous people at the periphery of imperial states and nations across the continent.In Part 1, “Homelands,” Hall provides an overview of Blackfoot history and culture through the eighteenth century. During the 1720s, they first received European trade goods, including hatchets, kettles, iron arrowheads, and some firearms, indirectly from Hudson Bay Company (HBC) fur traders via Cree and Assiniboine middlemen, and soon after they acquired horses through Native groups to the south and west. Metal goods and horses proved to be double-edged swords, Hall maintains, transforming the daily lives of Blackfoot men and women by facilitating hunting, hide preparing, wealth acquisition, and movement, but also escalating intertribal warfare and the Indian slave trade. Following a devastating smallpox epidemic in 1782, Blackfoot traders, who had begun to receive more significant numbers of European guns by the 1760s and 1770s, established direct trade ties with British HBC and Canadian North West Company (NWC) traders, thus lowering the trade prices of the products they received by eliminating Cree and Assiniboine middlemen. By denying their southern and western neighbors access to British and Canadian firearms, the Blackfoot were able to maintain dominance over horse-rich Shoshones, Flatheads, and many other Native groups through 1800.Part 2, “Boundaries,” describes how the Blackfoot people and their Gros Ventre allies responded to the Lewis and Clark expedition by using violence and intimidation to restrict US trade and expansion in the region and preserve their own superiority over outsiders and Native competitors through the 1820s. In the spring of 1831, a decade after the damaging merger of the NWC with the HBC, Blackfoot leaders shifted their strategy to diplomacy, inviting American Fur Company traders to establish a trading post on the Upper Missouri River within their territory. This enabled the Blackfoot to once again play their outside trading partners off of one other and, according to the author, remain “the most powerful and prosperous people on the northwest plains” through the mid-nineteenth century (p. 114).Finally, in Part 3, “Collisions,” Hall shows how shrinking game populations and US territorial expansion led to a crisis for the Blackfoot between 1848 and 1870. Seeking to use bison diplomacy to keep enemy Crees, Lakotas, Assiniboines, Flatheads, and Shoshones from hunting in their homelands, in October 1855 Blackfoot leaders joined their Gros Ventre allies in signing “their first (and only) treaty with the U.S. government” (p. 120). But the results revealed a diminishment of Blackfoot power, for their chiefs agreed to maintain peace and share hunting grounds with all of their neighbors in the southern and western portions of their territory, and they permitted US citizens to pass freely through Blackfoot country, utilize its resources, and settle there in exchange for promised annuity goods and “promotions of the Indians’ civilization” (p. 137). Tensions continued to escalate during the 1860s, as many Blackfoot warriors responded to disorderly and untrustworthy Indian agents, trespassing gold miners, disease outbreaks, and the decline of the fur trade by increasing their horse and resource raids. This, in turn, increased settler violence and nativism, particularly in Montana Territory, where in 1870 US troops under Major Eugene Baker unjustly slaughtered two hundred Piikanis in the Marias Massacre.The strengths of this well-written, well-researched book vastly outweigh its weaknesses. Although Hall did not contact Blackfoot people directly, he makes excellent use of Blackfoot written sources, particularly winter counts and Blackfoot orthography, and he conducted extensive archival research in four Canadian provinces, five US states, and Washington, DC. The subtitle could have been more geographically specific, and the author tends to mention Blackfoot challenges, such as the fact that Edmonton was in Cree territory after 1837, anachronistically at the beginning of ensuing chapters. Nevertheless, the broad transcontinental and comparative context Hall provides to the remarkable Blackfoot story makes this book well-suited for scholars and graduate students of Indigenous, Borderlands, and Western North American history.