It is easy to understand why modern historians, trained in the Roman way of thinking and seeking to associate all institutions with Rome, find it so difficult to appreciate the communalist movement that existed in the eleventh and twelfth centuries. This movement with its virile affirmation of the individual, and which succeeded in creating a society through the free federation of men, of villages and of towns, was the complete negation of the unitarian, centralizing Roman outlook with which history is explained in our university curricula. Nor is it linked to any historic personality, or to any central institution. It is a natural development, belonging, just as did the tribe and the village community, to a certain phase in human evolution, and not to any particular nation or region. This is the reason why academic science cannot be sensitive to its spirit and why the Augustin Thierrys and the Sismondis, historians who really had understood the mood of the period...