This book springs from parallel interests in a class of puzzling historical events, and a particular form of large-scale social causation. The first refers to the ability of small minorities of people in control of a twentieth-century state apparatus to dominate large majorities. In the most general sense, this phenomenon of popular subordination can be seen as the type of dependent variable or class of outcomes to be addressed. The second interest is how historical, structural and institutional contexts influence the ways people engage in political contention. In the most general sense this form of causation can be seen as the independent variable.