Ambush! Battle with the Nervii
Julius Caesar’s campaign against the Belgae began with impressive success. He defeated and demoralized a great host of enemies nearly 250,000 men strong. As summer was the prescribed season for war and the year was still young, Caesar moved his forces North-Northwest toward the Belgae tribe Nervii, of whom a reputation of fierceness and unwavering resistance against Rome had been reported. So, towards their border he marched. After three days, some Belgaen prisoners fled Caesar’s camp in middle of the night and told the Nervii of the Roman manner of approach. Specifically, that in between each legion was a baggage train, so that while they marched during the day there would ample opportunity to attack the Roman army while they are separated by long packs of supplies, servants, and animals, disjointed and vulnerable.
As the Romans neared their destination – the River Sabis (Modern: Sambre River) 10 miles into the Nervii territory – Caesar reorganized his legion’s marching orders, as was customary, to have his six legions up front, the baggage train behind them, with then the two newest legions in rear-guard behind that. This was contrary to the alternating legion-baggage train, legion-baggage train arrangement that the Nervii were expecting.
The Romans then ended their march and selected a site for their camp atop a hill, which sloped down till the bank of the River Sabis. On the other side of the river was a similar hill, wooded dense with trees. Around the base of that opposing hill were some Nervii cavalry visible to the Romans. Above them, hidden in the woods were the reputable Nervii infantry. Roman cavalry and ranged troops were ordered to cross the river and engage with that visible contingent of Nervii cavalry while the rest of the legions set up camp.
Upon seeing the baggage train arrive behind the sixth legion, the Nervii saw instance to initiate their ambush, not realizing they were facing the mainstay of the Roman army. However, the ambush was still highly effective.
The Nervii from the opposing hill charged down over the river and up at the Romans. The hilltop was forested so freedom of movement was restricted. And the Romans had largely broken rank as they busied about camp-work making communication even more challenging once the onslaught began. Caesar attempted to rally his troops, riding among them with speech and flag, but such sudden action had already caused disarray. Coordination was difficult. The attack surely could have led to a total rout if not for the experience and training of the Roman officers and centurions who were able to react reasonably well in independent command of their assigned regiments to stave off the swarming attackers.
The legions were so separated that it largely fell on the centuries – the smallest suborder of a Roman legion made up of 80-100 infantry led by one centurion – to fight their way back to each other and reform. Only then, once all together again, could they mount a proper defense against the overwhelming battery. Some of the auxiliary forces in Caesar’s army – troops comprised of Gallic recruits and foreign soldiers – scattered in panic and flight as more and more Nervii charged up the hill and entered the Roman camp.
What else should I make of this ambush but to give credit to the Nervii? They had to charge uphill to launch their attack and did so successfully. But, the courage and experience of the Roman army took credit for a successful defense because they held ground long enough for the tides to turn.
First, Caesar managed to gradually reform the legions closer together.
Then, the leader of the Roman cavalry who had been sent to engage the lingering Nervii cavalry on the other side of the river had advanced and taken the Nervii camp and then sent the Tenth Legion that had accompanied him to return to Caesar to help. And return they did, tarrying not, but in haste brought valuable support to the Roman camp.
Finally, the last two legions arrived behind the baggage train. At which point, the momentum shifted immensely. An organized Roman army was the most formidable force of power our ancient world had ever known. Once reorganized, the Romans were then able to stand their ground against the ambush and cut the enemy down to size.
The Nervii began throwing their last volleys of offense as they stood upon the heaped up bodies of their slain brethren. Valiant though they were, their entire tribe was nearly destroyed. What remained of the 60,000 armed Nervii were 5,000 armed men, plus the Nervii elders, women, and children. The number of civilians went unaccounted for in Caesar’s express accounts.
Upon their surrender, Julius Caesar showed mercy and let the survivors remain in their territory. He ordered the neighboring Belgae tribes to leave them alone to rebuild in peace. Here, we see Caesar exercising de facto governance over the region as he assumed a position of authority over the surrounding Belgae tribes as well as the Nervii. And he would aim to wave that arm of authority over the remaining Belgae tribes as well.