Nobles and barbarians, civilized nations and uncivilized tribes, conquered and unconquered,—so the world was divided in the golden age of the Roman Empire, when the city on the seven hills ruled the world, when it was the proudest boast a man could make to say, "I am a Roman citizen," and he who could claim that right looked on the subject peoples of the north and west and south and east and called them barbarians, while under his breath he termed them slaves.
Thus it was in the days of the great Cæsars, and it was a wise order of things for a time, for so the whole known world was drawn together into a huge framework of law and civilization; so it came about that the great waters were guarded by Roman transports, and merchants might journey over them in safety, and commerce prospered; and so it was that great highways were built across the continent of Europe, until the saying was that "all roads led to Rome."
But there was one region where Roman roads did not penetrate, and where, though legions of trained soldiers marched and countermarched, they did not stay nor hold a lasting place. Down through the map of Europe run two rivers, in the north the Rhine and in the south the Danube, forming a natural boundary which separates the great forests of Germany and Austria and Hungary from the western plains and peninsulas; and this boundary stood as the frontier, the limit of the Roman Empire.
It had not been the wish of the great mistress of the nations that she should stop here; it was the dream of Roman emperors that she should rule the world from the rising of the sun to its setting; but here she had been forced to pause, and the reason why she stopped her imperial progress is told in the first story of the conflict between barbarian and noble.