A young generation of historians is finally focusing on the long-neglected watershed years between the late eighteenth and the mid-nineteenth centuries, when nation-states emerged from the wreckage of Spanish and Portuguese empires. Looking beyond the traditional diplomatic accounts and Marxist-influenced economic interpretations, these two scholars try to explain the different courses that nation building took in the Americas. Vinson examines the role of Mexico's free colored militia as a prism to analyze race relations and mobility in a period when nearly ten percent of Mexicans had African ancestry. Through a remarkable exploration of archival material, he follows the lives of tens of thousands of soldiers who served as volunteers or conscripts. Kraay, meanwhile, delineates an interesting Brazilian counterpoint to the Mexican case. Also focusing on military institutions, he looks at Bahia, one of Latin America's principal slave plantation regions, where the armed forces were organized into racially segregated military units to reflect Brazil's class and race hierarchies. He follows these units' trajectories through the independence struggles and their incorporation into the Brazilian national state by the 1840s. Kraay also examines how the National Guard evolved from a local organization into an arm of the central government, undermining the once-close connections between soldiers and local society. Through these histories, Kraay neatly demonstrates how the Brazilian state was reconstructed and centralized over the course of the nineteenth century.