We began this book because we wanted to understand the evolution of political regimes in Latin America since 1900 and the reasons for the patterns of those political regimes. What explains why democracies have endured or broken down? What explains why dictatorships have survived or fallen? What explains waves of regime change? Even though the literature had many rich case studies, it was not entirely clear how to cumulate knowledge from these existing studies. Nobody had previously undertaken a project to explain the emergence, survival, and fall of democracies and dictatorships for the region as a whole over an extended period of time.

These empirical issues raised theoretical questions. What theories or theoretical approaches gave us the most leverage in understanding the emergence, survival, and fall of democracies and dictatorships in Latin America? From the outset, we were skeptical that some prominent existing theories would give us much leverage for explaining these issues for Latin America. Modernization theory, which posits that more economically developed countries are more likely to be democratic, did not seem promising as a way of understanding the vicissitudes of democracies and dictatorships in Latin America. A decade ago, we published an article that showed a weak and nonlinear relationship between the level of development and democracy in Latin America (Mainwaring and Pérez-Liñán 2003). Our work added to earlier evidence that modernization theory did not go far toward explaining political regimes in Latin America (Landman 1999; O’Donnell 1973).