The Battle of the Sabis or Sambre:
The Nervii were the largest remaining hostile tribe. They were stationed with the Trebates, Viromandui on the far side of the Sabis river. They were expecting the Atuabantes. Both sides had informants, so the Nervii knew how the Romans traveled. The Romans were vulnerable while on the march. The Nervii gave evidence that they would challenge Caesar's crossing, so Caesar rearranged his troops so that experienced legions would be together; the baggage and the two new legions apart. When they stopped, most of the men worked on the campsite so it could be done as quickly as possible. This left the Romans unarmed.
The Nervii Attack:
As soon as the Nervii sighted the baggage trains, they rushed from their hiding places, routed the Roman cavalry and then attacked the men working on building the camp. There was no time for the Romans to prepare for battle. Instead, the leaders gathered together those men who were nearest. Caesar ordered the 10th Legion to charge and so halt the Atrebantes. Other legions were making headway against the Viromandui, but most of the Nervii were on the Roman right flank, where the Romans were not holding their own. Caesar grabbed a shield and ran up to the front line, yelling encouragement to his men.
The Battle Turns:
While Caesar inspired the fighters, it was another event that turned the tide and let the Romans win. The Nervii caught site of the two new legions who had been behind the baggage train. They were still fresh, encouraging to Romans and discouraging to battle-weary Belgians. The 10th legion went after the Nervii from their rear and the new legions joined the fighting. The Nervii continued to fight for a long time. When they surrendered, Caesar ordered them to stay within their own territories.
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