This is a groundbreaking piece of scholarship, packed with evidence in support of fresh interpretations of the consolidation of Mexico's single party–dominated political system. If the results are well known, the processes by which they were achieved are much less so. Paul Gillingham's extensive work to explain them is a gift to the field of Mexican history.Gillingham is tireless in his delivery of decades of research and interpretation—skip a page at the peril of missing something genuinely important. He expects a relatively high degree of previous knowledge from his readers, in exchange for a generous payout: a much better and more complete understanding of Mexico's so-called “dictablanda.” His most important findings concern elections, violence, and demilitarization, based on close examination of two states, Guerrero and Veracruz, largely focused on 1945–50, which he argues was a watershed period for Mexico's political development for numerous reasons. The first two chapters introduce the two states, while subsequent chapters address the larger conclusions that Gillingham draws from his case studies: of how the Institutional Revolutionary Party (PRI) consolidated its power and the many compromises that this required.Rather than a revolution that gradually institutionalized, Gillingham shows us one in retreat, as various groups and individuals at all levels of politics availed themselves of institutional mechanisms, as well as extralegal and violent ones, to undo a brief period of political and economic revindication of working people. Yet, he cautions us, conciliation and compromise at the grassroots were still necessary, especially at the state and local levels. Electoral monopoly by the PRI was often the outcome of fixed or overturned elections, but also of violence, intimidation, low popular turnout, and the disempowerment of popular forces. Rather than by winning hearts and minds, the early PRI succeeded in part because many citizens gave up on voting entirely. But Gillingham also emphasizes that even at the peak of PRI hegemony, in many places there were “jostling, angry crowds beneath a soft authoritarian surface” to which the party was always to some degree answerable (p. 160). This was particularly true at the local level, where municipal elections, usually too much trouble for the state to either control or overturn, sometimes remained genuinely contested.Gillingham gives us a nuanced picture of the highly particular nature of Mexican postrevolutionary authoritarianism and its diverse practices, including his interpretation of why Mexico did not succumb to military authoritarianism, long the main pillar sustaining arguments about the country's exceptionalism within Latin America. He significantly complicates this story and argues that while Mexico's military was relatively small, its various functions (particularly policing and other forms of social control) remained critically important, and its members remained legally and often politically protected when they defied the law and the constitution; what's more, some of them became both powerful and wealthy in the process. Thus, this was a much less complete and a more fraught demilitarization than is often recognized. Again, Gillingham identifies 1945–50 as a critical turning point, when civilian governance was definitively confirmed—for a series of interesting reasons, and at significant costs, especially the state giving the army a lot of autonomy. And he underscores that while no general became president after 1946, four of them led the PRI in the years that followed (p. 269).Gillingham draws larger conclusions about Mexico grounded in study of two states thanks to an impressive body of archival and secondary research, supported with additional evidence from all over the country. His engagement with primary and secondary sources is both deep and masterful. Mexican history has long been regionalized, but Gillingham makes abundantly clear the national stakes of regional studies; indeed, some of his most important arguments concern the relationships between Mexico City and the provinces, down to the local level. It takes both great expertise and extraordinary patience to establish context and tease meaning out of complex local conflicts, and Gillingham does it repeatedly throughout the entire work. He also makes some revelatory comparisons with other countries; the most stunning of these is his comparison of levels of violence in Mexico and Colombia in these same years, during La Violencia. The PRI, he argues, inarguably used violence to achieve its rule, but by the 1950s, for a multiplicity of reasons, Mexico was becoming notably less violent (although readers are likely to be astonished by his findings about its murder rates at midcentury).Whether Mexico in those years was “unrevolutionary” or merely postrevolutionary, the subtitle is, in the end, misleading. Gillingham does not show us a dictatorship at all but something much more complicated, and much more interesting (if also impossible to succinctly define, as he readily acknowledges). Written clearly and argued compellingly, this is a work that will be vitally important for graduate students and scholars of Mexico and of twentieth-century authoritarianism for the foreseeable future.