In 57 BC the Belgae people of Gaul were mobilizing against the Romans. The Sambre was the final battle of the campaign against them. I have chosen to depict it here because Caesar described the proceedings of battle in such high detail, thus making it easy to reenact it in an accurate way.
The Bellovaci, Suessiones, Nervii, Atrebates, Ambriani, Morini, Menapii, Caleti, Veliocasses, Viromandui, Aduatuci, Condrusi, Eburones, Caeroesi, and Paemani tribes had united to push out the Romans. They were lead by a man named Galba, king of the Suessiones. The Remi, a Belgic tribe sympathetic to Rome, warned Caesar of the impending rebellion. Caesar readied his troops and ordered the Aedui tribe to raid the Bellovaci territory.
The fighting began when the Belgae forces attacked the Remi town of Bibrax. To relieve the town, Caesar sent a force of Auxiliaries: Balearic slingers, and Numidian and Cretan archers. Upon their arrival, the Belgae broke the siege and marched toward Caesars main camp, stopping 2 miles away. There were a few cavalry skirmishes designed to test the Belgae. Caesar ordered his men to dig ditches 400 paces long to protect each flank. Outposts with artillery were built at the ends of these ditches. Two legions remained to guard the camp while the other six formed up for battle. There was a marsh in between the Belgae and the Romans. Neither side wanted to cross against this disadvantageous land. So, the Belgae decided that each tribe would return to protect their own territory individually. Their departure was very un-organized. The Romans killed many as the Belgae retreated.
Shortly after, the Romans laid siege to the Suessione town of Noviounum. They surrendered. Caesar then lead his men against the Bellovaci. They also surrendered. The Ambriani surrendered as well. So, the Belgic union disintegrated. However, the Nervii tribe was intent on continuing the fight. They were a very isolationist people, unwilling to ally with this foreign power of Rome. Lead by a man named Boduognatus, they were joined by the Atrebates, Viromandui. Aduatuci. Their forces had formed against the Romans opposite of the river Sambre. The Aduatrici were on their way to help them.
THE BATTLE OF THE SAMBRE
The river was about 3 feet deep. The land on the side of the Nervii was clear and open for about 200 paces, but it sloped up into a wooded area. The Roman side also had a hill which sloped evenly down to the river. Caesar learned where the Nervii were when he was about nine miles away. The Belgic forces were waiting in the woods as the Romans began to march in. Caesar had sent cavalry along with light infantry, archers and slingers across the river to engage the Belgic cavalry. The Belgic cavalry would flee into the woods, rush out to attack and return to the safety of the woods again. The Romans did not dare to pursue them into the closed quarters of the forest. When the Bervii forces saw the Roman baggage coming in they rushed out of the forest in full force. The Roman cavalry was scattered as the Nervii bolted across the river to meet the main force of Romans.
The Romans in camp were taken completely by surprise. Few had enough time to even put on their helmets or uncover their shields. The IX and X legions were on the Roman left flank. They met the Atrebates on higher ground and managed to push them back across the river. The legions crossed the river and defeated the enemy there. Legio XI and VIII fought the Viromandui in the center and also managed to force them back toward the river. Boduognatus lead his Nervii infantry (they had no cavalry) in a dense column squeezing through the Roman line into the camp. The Treveri cavalry arrived to help Caesar, but when they saw the camp over-run, they went home. The XIII and XIV legions were in the rear guarding the baggage train. When they learned of the fighting they rushed in to join the fighting. Titus Labienus was commanding the legions who had made it into the Belgic camp. He sent the X legion back across to help. This renewed the spirits of the Romans, who up till that time were fighting desperately. The Roman then cavalry rejoined the fight attempting to make up for their early defeat. The Belgae were wiped out. The Aduatuci arrived too late to help the Belgae, so they returned home.References:
1. The Gallic War by Julius Caesar. translated by H. J. Edwards