The last quarter of the twentieth century is marked by two important events: the rise of political Islam and the collapse of communism. One can trace the origins and the rise of political Islam to the victory of the Islamic revolution in Iran (1978-79) and the origins of the collapse of communism to Solidarity revolution in Poland (1980-81). This article explores these two revolutions and sheds light on certain similarities and differences. It specifically focuses on two aspects, challenging the existing theories of revolution. The first is what they have in common, i.e., the important albeit a different role that religion played in both revolutions. The second aspect explores the differences in the revolutionary processes, as the Iranian case concluded in uncompromising introduction of terror after its victory whereas Solidarnosc was from the beginning peaceful and willing to negotiate its demands with the authorities, and ultimately compromised to share power with the communists.