Please note that Mommsen uses the AUC chronology (Ab Urbe Condita), i.e. from the founding of the City of Rome. You can use this reference table to have the B.C. dates
From: The History of Rome, by Theodor Mommsen
Translated with the sanction of the author by William Purdie Dickson
Ariovistus Attacked - And Beaten
It was the more necessary not to delay; Caesar immediately set out against Ariovistus. A panic seized his troops, especially his officers when they were to measure their strength with the flower of the German troops that for fourteen years had not come under shelter of a roof: it seemed as if the deep decay of Roman moral and military discipline would assert itself and provoke desertion and mutiny even in Caesar's camp. But the general, while declaring that in case of need he would march with the tenth legion alone against the enemy, knew not merely how to influence these by such an appeal to honour, but also how to bind the other regiments to their eagles by warlike emulation, and to inspire the troops with something of his own energy.
Without leaving them time for reflection, he led them onward in rapid marches, and fortunately anticipated Ariovistus in the occupation of Vesontio (Besancon), the capital of the Sequani. A personal conference between the two generals, which took place at the request of Ariovistus, seemed as if solely meant to cover an attempt against the person of Caesar; arms alone could decide between the two oppressors of Gaul. The war came temporarily to a stand. In lower Alsace somewhere in the region of Muhlhausen, five miles from the Rhine,(36) the two armies lay at a little distance from each other, till Ariovistus with his very superior force succeeded in marching past the Roman camp, placing himself in its rear, and cutting off the Romans from their base and their supplies.
36. Goler (Caesars gall. Krieg, p. 45, etc.) thinks that he has found the field of battle at Cernay not far from Muhlhausen, which, on the whole, agrees with Napoleon's (Precis, p. 35) placing of the battle-field in the district of Belfort. This hypothesis, although not certain, suits the circumstances of the case; for the fact that Caesar required seven days' march for the short space from Besancon to that point, is explained by his own remark (i. 41) that he had taken a circuit of fifty miles to avoid the mountain paths; and the whole description of the pursuit continued as far as the Rhine, and evidently not lasting for several days but ending on the very day of the battle, decides--the authority of tradition being equally balanced--in favour of the view that the battle was fought five, not fifty, miles from the Rhine.
The proposal of Rustow (-Einleitung zu Caesars Comm-. p. 117) to transfer the field of battle to the upper Saar rests on a misunderstanding. The corn expected from the Sequani, Leuci, Lingones was not to come to the Roman army in the course of their march against Ariovistus, but to be delivered at Besancon before their departure, and taken by the troops along with them; as is clearly apparent from the fact that Caesar, while pointing his troops to those supplies, comforts them at the same time with the hope of corn to be brought in on the route. From Besancon Caesar commanded the region of Langres and Epinal, and, as may be well conceived, preferred to levy his requisitions there rather than in the exhausted districts from which he came.
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