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
They still lay, apparently, in the region of Nimeguen and Cleves; but it was said that, following the invitations of the Celtic patriot party, they intended to advance into the interior of Gaul; and the rumour was confirmed by the fact that bands of their horsemen already roamed as far as the borders of the Treveri. But when Caesar with his legions arrived opposite to them, the sorely- harassed emigrants seemed not desirous of fresh conflicts, but very ready to accept land from the Romans and to till it in peace under their supremacy. While negotiations as to this were going on, a suspicion arose in the mind of the Roman general that the Germans only sought to gain time till the bands of horsemen sent out by them had returned.
Whether this suspicion was well founded or not, we cannot tell; but confirmed in it by an attack, which in spite of the de facto suspension of arms a troop of the enemy made on his vanguard, and exasperated by the severe loss thereby sustained, Caesar believed himself entitled to disregard every consideration of international law. When on the second morning the princes and elders of the Germans appeared in the Roman camp to apologize for the attack made without their knowledge, they were arrested, and the multitude anticipating no assault and deprived of their leaders were suddenly fallen upon by the Roman army. It was rather a manhunt than a battle; those that did not fall under the swords of the Romans were drowned in the Rhine; almost none but the divisions detached at the time of the attack escaped the massacre and succeeded in recrossing the Rhine, where the Sugambri gave them an asylu in their territory, apparently on the Lippe. The behaviour of Caesar towards these German immigrants met with severe and just censure in the senate; but, however little it can be excused, the German encroachments were emphatically checked by the terror which it occasioned.
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