It is not possible to understand Ivan iv and his policies, Charles Halperin emphasizes, without taking into account Muscovite political, economic, social, and cultural history. To explain the mass terror that characterized the oprichnina, Halperin delves particularly into social history and finds the roots of the terror in the establishment and enlargement of the gentry, which entailed a high degree of social mobility. Without any mechanisms for releasing the anxiety produced by social mobility, social pressures mounted until the establishment of the oprichnina provided an opportunity for the gentry to release their frustrations in unrestrained violence. An inquiry into a wider range of social and economic developments reveals that the gentry had to deal with stress arising from multiple sources, more disturbing and persistent than social mobility. It also indicates that the gentry did have mechanisms at their disposal to express and alleviate their anxieties. This inquiry does not confirm or reject Halperin’s conclusion that gentry oprichniki, contravening Ivan’s intent, were responsible for unleashing mass terror. It does suggest that to discover the roots of the gentry’s actions it may be necessary to consider a wider range of factors in Muscovy’s complex, dynamic social and economic history.