The battle of Faesulae (225 BC) was a Gallic victory over a Roman army that had been following them as the Gauls advanced towards Rome. However the arrival of a second Roman army late in the day convinced the Gauls to retreat north with their booty, and during the retreat they were trapped between this and a third Roman army and destroyed at the battle of Telamon (Telamon War).
Over the previous few years both sides had been preparing for war. The Boii and Insubres, two Gallic tribes from the Po Valley, had arranged an alliance with the Gaesatae, mercenaries from the Alps and Transalpine Gaul, and the Taurisci, from the slopes of the Alps. Polybius gives them a total of 50,000 infantry and 20,000 cavalry, while Diodorus gave them 200,000 men.
The Romans had also been busy. They had raised five separate armies – two commanded by the consuls for the year, one made up of Italian allies, one made up of a mix of Italians from the Apennines and Gauls from the north-east and a reserve army based at Rome. The two consuls each commanded 50,800 infantry and 3,200 cavalry, including four Roman legions and a power force of allies. C. Atilius Regulus was sent to Sardinia, possibly to deal with a revolt, while L. Aemilius Papus was sent to Arimunum on the Adriatic coast, to block the most likely invasion route. The army of Italian allies, which contained 50,000 infantry and 4,000 cavalry from the Etruscans and Sabines, commanded by an unnamed Praetor, was sent to the borders of Etruria to guard against any invasion west of the Apennines. The mixed Allied and Gallic army probably operated somewhere in the north-east, threatening the Gallic lands from the east.
When the Gallic invasion began they caught the Romans out of position by crossing the Apennines and invading Etruria. They were able to get past the Praetor’s army and were able to advance south towards Rome, ravaging the country as they went, seizing large numbers of slaves, cattle and other booty. The Romans reacted by sending messages to the two consuls, summoning them to deal with the threat, while the Praetor followed them south. We don’t know what actually happened when the Gauls first invaded – if they were allowed to pass by the Praetor to give time for the consuls to arrive, or if he avoided battle because his army of Roman allies was badly outnumbered, or if he was simply in the wrong place when the Gauls attacked. The nature of the booty the Gauls had captured also suggests that they weren’t moving terribly fast, which gave the Romans the chance to get their armies back into place. By the time the Gauls were approaching Rome, three Roman armies with around 150,000 men were closing in on them, not to mention the reserves at Rome.
The Gauls got as far as Clusium, three days to the north of Rome, when they discovered that the Praetor was following them and wasn’t too far off. They decided to turn back north to deal with this threat. Polybius’s account jumps straight from this decision to the eve of the battle, which he places at Faesulae. The only known town of this name was eighty miles to the north, suggesting either that several days have been omitted from this account, one of the locations is incorrect or there was another Faesulae that is no longer known.
At sunset on the evening before the battle the Gauls and the Praetor’s army were camped in close proximity, while Aemilius was just under a day’s march away. The Gauls decided to trick the Romans into an ambush. Their infantry retreated to Faesulae, leaving the camp fires burning and the cavalry in their original camp with orders to follow on and draw the Romans into a trap. On the following morning the Romans saw the camp empty apart from the cavalry and assumed that the Gauls had fled. When the cavalry also moved off, the Romans followed them as fast as possible, presumably losing getting a bit spread out during the pursuit. As they approached Faesulea the Gauls came out of their position and attacked the Romans. At first the Etruscans and Sabines resisted fiercely, but eventually a combination of superior Gallic numbers and courage saw the Roman army forced into retreat. According to Polybius 6,000 ‘Romans’ were killed. Most of the survivors fled to a nearby hill that was a strong defensive position.
The Gauls followed the retreating Romans, and attempted to attack them in their new position. However by now Gauls were tired after the long night march and the first part of the battle, and they began to suffer heavier losses than the besieged Romans. The Gauls withdrew to a new camp, leaving their cavalry to guard the defeated Romans. Their plan was to return on the following day and renew the siege.
The Romans were saved by the arrival of the Consul Aemilius Papius, who reached the area on the evening after the battle and camped nearby. Both the Gauls and the Praetor’s defeated army saw the new campfires and realised what it meant. The besieged Romans were able to get messengers through the Gallic cavalry lines. Aemilius decided to act immediately. His tribunes were ordered to wait until the morning and then attack with his infantry, while Aemilius himself immediately led his cavalry towards the besieged Praetorian force. Presumably he was easily able to get through the Gallic cavalry cordon, but Polybius is silent on what actually happened.
On the Gallic side the arrival of a fresh Roman army triggered a council of war. Famously such councils rarely decide to stand and fight, and the outcome of this one was no different. Aneroestus, one of the leaders of the Gaesatae, argued that it wasn’t worth risking losing the massive amount of booty that they had captured so far, and instead they should return north, take their spoils back to the Gallic lands, and then turn back to deal with the Romans when they weren’t encumbered with a massive quantity of slaves, cattle and other spoils. Quite what the Romans would be doing while the Gauls were slowly plodding north with their booty isn’t clear. However Aneroestus was able to win over the council (or possibly simply threaten to leave), and the Gauls broke camp that night and began to retreat north along the coast.
On the following morning Aemilius was thus able to unite his intact army with the survivors of the Praetorian army. In theory he could now have outnumbered the Gauls – if Polybius’s figure of 70,000 for the invasion force is correct, then Aemilius now had his own 50,000 men and the survivors of the Praetor’s 54,000, although we don’t know how many of them actually stayed to be besieged and how many simply fled. However he decided not to risk attacking the Gauls and instead followed them north, waiting for the right moment to strike. Presumably he was also aware that C. Atilius Regulus was on his way back from Sardinia and the Gauls would soon be trapped between two Roman armies. This was indeed what happened, and the retreating Gauls suffered a crushing defeat at the battle of Telamon.