At no time during the past century has European society been closer to major revolutionary upheaval than at the close of World War I. That in the end the Russian Revolution was contained and “world revolution” averted has been related by historians to any number of factors. Yet one of the most important reasons for the ebbing of the revolutionary tide has generally been overlooked or passed over lightly. This was the failure of the revolutionary movement, except in Russia, to secure really significant support from a particular segment of the working classes, namely women. A more classic case of the historian's tendency to accept sex as a constant, i.e., to operate in general as if only one sex—the male sex—exists, would be difficult to find. In fact an individual's sex can be an important variable in political behavior and like age, occupation, religion, and a variety of other social, economic, and cultural factors, something which needs to be considered much more carefully in order to arrive at a better understanding of the past.