The great revolutions of modern times have been analysed from various angles, but their civilizational aspects and contexts have on the whole been neglected. More specifically, the major 20th-century revolutions can be seen as particularly important cases of intercivilizational encounters. They represent different responses to the ascendant and challenging civilization of the West. The Western civilizational trajectory (or set of trajectories), based on a shift from fideism to empiricism and on multiple social dynamics fuelled by this cultural reorientation (such as (...) those of the capittalist economy and the one-nation-state), is selectively appropriated by non-Western societies which at the same time reject the less adaptable parts of the West in the name of traditional or invented alternatives. Russia, China, Turkey and Iran are analysed as variations of this recurrent pattern. At one end of the spectrum, the Russian revolution aspired to transcend Western models on the basis of a more radical interpretation of their own principles; at the other, the Iranian revolution, made up of several episodes with intervals in between, has been characterized by an exceptionally tenacious - and in some ways inventive - defence of a pre-existing civilizational identity. (shrink)