From the outset we meet one basic fact, so difficult to realise when France is considered as one country, the essential difference between the North and the South. Caesar found in the South a partial Roman civilisation ready for his organisation; and old, flourishing cities, like Narbonne, Aix, and Marseilles. In the North he found the people advanced no further than the tribal stage, and Paris--not even Paris in name--was a collection of mud huts, which, from its strategic position, he elevated into a camp. The two following centuries, the height of Roman dominion in France, accentuated these differences. The North was governed by the Romans, never assimilated nor civilised by them. The South eagerly absorbed all the culture of the Imperial City; her religions and her pleasures, her beautiful Temples and great Amphitheatres, finally her morals and effeminacy, till in the II century of our era, anyone living a life of luxurious gaiety was popularly said to have "set sail for Marseilles." To this day the South boasts that it was a very part of Rome, and Rome was not slow to recognise the claim. Gallic poets celebrated the glory of Augustus, a Gaul was the master of Quintilian, and Antoninus Pius, although born in the Imperial City, was by parentage a native of Nimes. [Illustration: "CARCASSONNE, THE INVULNERABLE."] Not to the rude North, but to this society, so pagan, so pleasure-loving, came the first missionaries of the new Christian faith, to meet in the arenas of Gaul the fate of their fellow-believers in Rome, to hide in subterranean caves and crypts, to endure, to persist, and finally to conquer. In the III and IV centuries many of the great Bishoprics were founded, Avignon, Narbonne, Lyons, Arles, and Saint-Paul-trois Chateaux among others; but these same years brought political changes which seemed to threaten both Church and State. Roman power was waning. Tribes from across the Rhine were gathering, massing in northern Gaul, and its spirit was antagonistic to the contentment of the rich Mediterranean provinces. The tribes were brave, ruthless, and barbarous. Peace was galling to their uncontrollable restlessness. The Gallo-Romans were artistic, literary, idle, and luxurious. They fell, first to milder but heretical foes; then to the fierce but orthodox Frank; and the story of succeeding years was a chronicle of wars. Like a great swarm of locusts, the Saracens--conquerors from India to Spain--came upon the South. They took Narbonne, Nimes, and even Carcassonne, the Invulnerable. They besieged Toulouse, and almost destroyed Bordeaux. Other cities, perhaps as great as these, were razed to the very earth and even their names are now forgotten. Europe was menaced; the South of France was all but destroyed.