This article examines the role of nationalism in the collapse of communism in the late 1980s and early 1990s, arguing that nationalism (both in its presence and its absence, and in the various conflicts and disorders that it unleashed) played an important role in structuring the way in which communism collapsed. Two institutions of international and cultural control in particular--the Warsaw Pact and ethnofederalism--played key roles in determining which communist regimes failed and which survived. The article argues that the collapse of communism was not a series of isolated, individual national stories of resistance but a set of interrelated streams of activity in which action in one context profoundly affected action in other contexts--part of a larger tide of assertions of national sovereignty that swept through the Soviet empire during this period.