France, under its modern name, was born around the year 1000 AD; but its territory, loosely delineated by the natural boundaries of mountains and rivers, was first marked out and unified by the Roman Conquest. For centuries it was only the strong tradition of national feeling that united this large amorphous body. France of the Modern Age was little more than an ideological concept. Its development as a more complex geographical area was not achieved until a relatively late date. The industrial revolution, the development of transportation, and increasing centralization led to the emergence of agricultural and industrial specialization, and the appearance of hierarchically ordered urban networks. The homogenization of the top cultural stratum had been assured by the Counter-Reformation and the main royal routes, but beneath this there was a profound diversity of popular culture. The fragmentations caused by the traumas of revolution brought about a religious and electoral geography which had astonishing cultural stability. Maximum diversification was achieved between 1875 and 1914 despite political centralization. In the twentieth century the picture becomes simpler. The second agricultural revolution has put paid to many regional specializations, and the triumph of the audiovisual is bringing about a profound unification of cultures and behaviours. The resulting unity will overwrite the fragmentations of the past.