But when we turn to history we find there is nothing definite on this most attractive subject till Cæsar arrives and makes personal observation. Speaking of the south—for he had not penetrated the northern parts—he tells us that he found two races in possession: one in the interior, which considered itself indigenous; the other on the sea-coast, roving adventurers from the Continent who arrived later. Tacitus, writing nearly a century and a half after Cæsar, namely, about 82 A.D., practically confirms Cæsar’s report of a double occupation, and adds the further interesting details, that the one race was dark complexioned and had curly hair, while the other, resembling the Gauls, had red hair and were tall of stature. In the eighth century A.D. we know, on the authority of Bede, that there were in these islands five written languages, viz. those of the Angles, the Brythons, the Scottis, the Picts, and the Latins, the first four[3] of which were spoken. It is the ever-puzzling yet fascinating work of philology and ethnology to trace the origin and exact racial connection of these—a work which hitherto has proved as elusive as the finding of the North Pole. Who are the dark complexioned race of the South? and who the Picts of the North? are questions of perennial interest to the experts. But though early British and German history is so elusive, we are on sure ground with the main facts of Celtic progress on the Continent from the fifth century B.C. Authentic history then opens with the advent of the classical writers just at the time when the Celts were entering upon a series of conquests which for the next 200 years made them the dominant race in Europe.[4] It is needless to follow their various migrations, even if it were possible. As their territories became congested on the Danube, they sent forth horde after horde of conquering tribes who surged every way. Now westward for the most part, till, in the graphic language of Galgacus, uttered centuries after, “there was now no nation beyond—nothing save the waves and the rocks” (Nulla jam gens ultra; nihil nisi fluctus et saxa), then, like the back-rushing tides, they receded eastwards. “Tumults,” the Romans called these irrepressible outbursts, and most felicitously too, for they were the terror of Europe. A cursory glance at some of the more famous of their invasions suffices to show the restless energy of the Celts and their far-reaching conquests.