them to render flight more difficult.  The right wing of the Romans, led by Caesar himself, threw itself rapidly on the enemy, and drove them before it; the right wing of the Germans was in like manner successful.  The balance still stood equal; but the tactics of the reserve, which had decided so many other conflicts with barbarians, decided the conflict with the Germans also in favour of the Romans; their third line, which Publius Crassus seasonably sent to render help, restored the battle on the left wing and thereby decided the victory.  The pursuit was continued to the Rhine; only a few, including the king, succeeded in escaping to the other bank (696).

German Settlements on the Left Bank of the Rhine

Thus brilliantly the Roman rule announced its advent to the mighty stream, which the Italian soldiers here saw for the first time; by a single fortunate battle the line of the Rhine was won.  The fate of the German settlements on the left bank of the Rhine lay in the hands of Caesar; the victor could destroy them, but he did not do so.  The neighbouring Celtic cantons—­the Sequani, Leuci, Mediomatrici—­were neither capable of self-defence nor trustworthy; the transplanted Germans promised to become not merely brave guardians of the frontier but also better subjects of Rome, for their nationality severed them from the Celts, and their own interest in the preservation of their newly-won settlements severed them from their countrymen across the Rhine, so that in their isolated position they could not avoid adhering to the central power.  Caesar here, as everywhere, preferred conquered foes to doubtful friends; he left the Germans settled by Ariovistus along the left bank of the Rhine—­the Triboci about Strassburg, the Nemetes about Spires, the Vangiones about Worms—­in possession of their new abodes, and entrusted them with the guarding of the Rhine-frontier against their countrymen.(37) The Suebi, who threatened the territory of the Treveri on the middle Rhine, on receiving news of the defeat of Ariovistus, again retreated into the interior of Germany; on which occasion they sustained considerable loss by the way at the hands of the adjoining tribes.

The Rhine Boundary

The consequences of this one campaign were immense; they were felt for many centuries after.  The Rhine had become the boundary of the Roman empire against the Germans.  In Gaul, which was no longer able to govern itself, the Romans had hitherto ruled on the south coast, while lately the Germans had attempted to establish themselves farther up.  The recent events had decided that Gaul was to succumb not merely in part but wholly to the Roman supremacy, and that the natural boundary presented by the mighty river was also to become the political boundary.  The senate in its better times had not rested, till the dominion of Rome had reached the natural bounds of Italy—­the Alps and the Mediterranean—­and its adjacent islands.  The enlarged empire also needed a similar military rounding off; but the present government left the matter to accident, and sought at most to see, not that the frontiers were capable of defence, but that they should not need to be defended directly by itself.  People felt that now another spirit and another arm began to guide the destinies of Rome.