Soviet acceptance of the collapse of East European Communist regimes in 1989 must be considered the single most significant event leading to the end of the Cold War. It provided the most compelling evidence of the magnitude of changes that were going on inside the USSR in 1989. Until then, the importance of Mikhail Gorbachev’s reforms was doubted in many places. Soviet behavior in 1989 in Eastern Europe was the definitive reality check of the “new thinking” in Soviet foreign policy.

Provocative as it may sound, it is not so much what happened in Eastern Europe itself in 1989 that was historically significant. The fragility of the Communist regimes there had been on the historical record for many years. It was Soviet tolerance for change that made the difference. Until Gorbachev’s reforms, Soviet domination of Eastern Europe had been internalized both in the East and in the West as an inescapable fact until some indeterminate future time. That is why the complete emancipation of Eastern Europe in 1989, while Soviet power was still intact, came as a breathtaking surprise in the West, in Eastern Europe itself, and even in the Soviet Union. The central argument of this chapter is that, while each revolution had specific national characteristics, their pace and scale were largely shaped by the gradual discovery of the scope of Soviet tolerance.