To the primitive population, the least known of all, that reared the stones of Carnac in France, and in England the gigantic circles of Stonehenge and Avebury, succeeded in both countries, many centuries before Christ, the Celtic race. The Celts ([Greek: keltai]) were thus called by the Greeks from the name of one of their principal tribes, in the same way as the French, English, Scottish, and German nations derive theirs from that of one of their principal tribes. They occupied, in the third century before our era, the greater part of Central Europe, of the France of to-day, of Spain, and of the British Isles. They were neighbours of the Greeks and Latins; the centre of their possessions was in Bavaria. From there, and not from Gaul, set out the expeditions by which Rome was taken, Delphi plundered, and a Phrygian province rebaptized Galatia. Celtic cemeteries abound throughout that region; the most remarkable of them was discovered, not in France, but at Hallstadt, near Salzburg, in Austria.[2] The language of the Celts was much nearer the Latin tongue than the Germanic idioms; it comprised several dialects, and amongst them the Gaulish, long spoken in Gaul, the Gaelic, the Welsh, and the Irish, still used in Scotland, Wales, and Ireland. The most important of the Celtic tribes, settled in the main island beyond the Channel, gave itself the name of Britons. Hence the name of Britain borne by the country, and indirectly that also of Great Britain, now the official appellation of England. The Britons appear to have emigrated from Gaul and established themselves among the other Celtic tribes already settled in the island, about the third century before Christ. During several hundred years, from the time of Pytheas to that of the Roman conquerors, the Mediterranean world remained ignorant of what took place among insular Britons, and we are scarcely better informed than they were. The centre of human civilisation had been moved from country to country round the great inland sea, having now reached Rome, without anything being known save that north of Gaul existed a vast country, surrounded by water, rich in tin mines, covered by forests, prairies, and morasses, from which dense mists arose.