- The consuls Quintus Fulvius Flaccus and Titus Manlius Torquatus subjugate the Boii, but the remainder of their campaign is unsuccessful (224 BCE);
- The consuls Gaius Flaminius and Publius Furius Philus win a decisive victory over the Insubres and are both awarded a triumph (223 BCE);
- The consul Gnaeus Cornelius Scipio Calvus besieges Acerrae while his colleague Marcus Claudius Marcellus races to Clastidium, which is threatened by the Insubres (222 BCE);
- At Clastidium, the Roman cavalry defeats the Celts, with Marcellus personally killing the enemy commander;
- Marcellus dedicates the spolia opima to Jupiter Feretrius in Rome;
- Scipio Calvus captures Mediolanum, the capital of the Insubres;
- Possible campaigns against the Histri (221 BCE);
- Hasdrubal Barcas is murdered in Spain. He is succeeded by Hannibal, Hamilcar Barcas’ son.
After their victory at Telamon in 225 BCE, the Romans went on the offensive. The consuls of 224 BCE, Quintus Fulvius Flaccus and Titus Manlius Torquatus were both given the war against the Boii as their province. With a large force, they invaded the territory of this tribe and managed to catch them by surprise and subjugate them for the moment. Their campaign later faltered because of bad weather and the outbreak of disease, but the Romans would be back next year.
Further campaigns: 223 BCE
The campaign of 223 BCE was again led by both consuls, Gaius Flaminius and Publius Furius Philus. Flaminius was a “new man” and this was his first consulship. The main target of the consuls was the territory of the Insubres, who lived further north than the Boii. Initially, the campaign did not go well. The Romans tried to cross the river Po (Padus in Latin) at its tributary the Adda (Addua in Latin), but they were repulsed by the Insubres. The consuls then marched their forces to the territory of their allies, the Cenomani. Approaching the Insubres from a different direction, the Romans were now confronted by a Celtic army which Polybius says numbered 50.000 men. The Romans themselves had two consular armies at their disposal, which means they had roughly 40.000 men in the field. Even if Polybius exaggerated again, the armies seem to have been evenly matched.
During the ensuing battle, the Romans employed a new tactic which does not seem to have been repeated in later battles, although it certainly proved successful. The hastati in the first ranks, who usually fought with javelins and swords, were now given the spears of the triarii of the third line. The hastati formed a dense phalanx formation, presenting the Celts with a tremendous spear wall. The Insubres charged the Roman lines, but were held at bay and did not succeed in cutting their way into the Roman formation with their large slashing swords. These swords were of high quality – although Polybius wrongly claimed otherwise – but lacked sharp tips, so they could not be used for stabbing, unlike the Roman swords. The Romans soon neutralised the Celtic charge and eventually began to push their adversaries back using their swords and shields. The Insubres were routed and most of them were killed. After their victory, the consuls returned to Rome laden with booty. They were both awarded a triumph.
A tradition hostile to Flaminius claims that the consul did not contribute much to the victory, which was instead won by his officers. Polybius even accused Flaminius of making a tactical mistake by deploying his men with their backs against the river, which could have led to disaster had the Romans been pushed back. Dio adds that the consuls had actually been summoned home by the Senate because of bad portents (Plutarch has a similar story). Furius was ready to comply, but Flaminius convinced him to continue the campaign. The latter according to Dio also “bestowed all the spoils upon the soldiers as a means of winning their favour”. After their return to Rome, the Senate wanted to charge the consuls with disobeying its commands, but Dio claims the popular assembly intervened, overruled the Senate and voted them a triumph instead.
We need to take most of the criticism mentioned above with a pinch of salt. Flaminius was unpopular among more conservative senators for the land reforms he initiated in 232 BCE. He had already been accused of populism. This certainly influenced the way he was portrayed in historical sources.
Further campaigns: 222 and 221 BCE
The Celts, presumably still the Insubres, now sued for peace, but the new consuls of 222 BCE, Marcus Claudius Marcellus and Gnaeus Cornelius Scipio Calvus, were eager to continue the conflict. Realising that a new Roman invasion was imminent, the Celts began recruiting fresh troops from across the Alps, with Polybius claiming that some 30.000 Gaesatae who were living along the Rhône joined their ranks. The Romans first moved against a fortified town called Acerrae, which Polybius says was “a city between the Po and the Alps”. Since the consuls had occupied all the strategic locations around the town, the Insubres had no choice but to stage a divisionary attack on the city of Clastidium (modern Casteggio in Lombardy), which was allied to Rome. While Scipio Calvus continued the siege of Acerrae, Marcus Claudius Marcellus rushed to the aid of Clastidium with just his cavalry and some of his light infantry.
At Clastidium, Marcellus was to win everlasting fame. The Romans were far outnumbered by the Celts, but the Roman commander was undeterred. At the head of his cavalry, he charged the Celtic horsemen and infantry. Before he had made contact, his horse suddenly shied, stopped and turned around. This could be seen as a bad omen, but the consul did not lose his nerve. Instead, he pretended to have wheeled his steed around on purpose, to be able to pray to the Sun. After his quick prayer, the consul and his men charged again. Plutarch tells us what happened next:
“Meanwhile the king of the Gauls [variously named Britomar(t)us or Viridomarus] espied him, and judging from his insignia that he was the commander, rode far out in front of the rest and confronted him, shouting challenges and brandishing his spear. His stature exceeded that of the other Gauls, and he was conspicuous for a suit of armour which was set off with gold and silver and bright colours and all sorts of broideries; it gleamed like lightning. Accordingly, as Marcellus surveyed the ranks of the enemy, this seemed to him to be the most beautiful armour, and he concluded that it was this which he had vowed to the god [i.e. Jupiter Feretrius, see below]. He therefore rushed upon the man, and by a thrust of his spear which pierced his adversary’s breastplate, and by the impact of his horse in full career, threw him, still living, upon the ground, where, with a second and third blow, he promptly killed him. Then leaping from his horse and laying his hands upon the armour of the dead, he looked towards heaven and said: “O Jupiter Feretrius, who beholdest the great deeds and exploits of generals and commanders in wars and fightings, I call thee to witness that I have overpowered and slain this man with my own hand, being the third Roman ruler and general so to slay a ruler and king, and that I dedicate to thee the first and most beautiful of the spoils. Do thou therefore grant us a like fortune as we prosecute the rest of the war.””
The Roman cavalry won a stunning victory over their Celtic opponents and caused both the enemy infantry and cavalry to flee. Having defeated the Celtic king in single combat, Marcellus was given the honour of dedicating the king’s arms and armour – the so-called spolia opima – to Jupiter Feretrius in his ancient temple on the Capitol Hill. This honour had so far only been bestowed on the legendary King Romulus himself and on one Aulus Cornelius Cossus in 437 BCE. Gnaeus Cornelius Scipio Calvus was now able to take Acerrae. From there he marched north to the capital of the Insubres, the city of Mediolanum (modern Milan). After some more fighting, Scipio Calvus managed to drive the enemy into the mountains. The consul gave chase, destroyed their lands and finally captured their capital. The Insubres were soundly defeated and sued for peace, which was granted.
The Roman campaigns of 221 BCE are poorly documented. Livius would have left us an account of these campaigns, but unfortunately this part of his work is lost. Dio claims the consuls Publius Cornelius Scipio Asina and Marcus Minucius Rufus “made an expedition in the direction of the Ister and subdued many of the nations there”. The Periochae mention a campaign against the Histri or Istrians, who were subdued. These claims are problematic. The Ister is the river Danube, which is way north of the Roman territories of this time. The Istrians, on the other hand, lived in Istria, which is a large peninsula in the Adriatic Sea that is nowadays part of Croatia (see the map above). If the consuls really got as far as Istria, it seems unlikely they managed to establish a Roman presence there. The Istrians would not be subdued until (new) Roman campaigns in 178 and 177 BCE.
Death of Hasdrubal
221 BCE also saw the death of the Carthaginian commander in Spain, Hasdrubal. Hasdrubal had continued where his father-in-law Hamilcar had left off. Using skilful diplomacy rather than blunt force, he had managed to greatly expand the Carthaginian territories on the Iberian peninsula. Hasdrubal did not die on the battlefield: he was murdered by a Celt who apparently held a grudge against the Carthaginian commander (Livius claims that Hasdrubal had killed his master). The army in Spain now elected 26-year-old Hannibal as Hasdrubal’s successor, a choice that was later ratified by the popular assembly back in Carthage. As a boy, he had been induced by his father to swear “never to be the friend of the Romans” (according to Polybius) or even to “be the declared enemy of the Roman People” (according to Livius). Hannibal soon got his first taste of battle as supreme commander. He successfully campaigned against a tribe named the Olcades before returning to his winter quarters in Carthago Nova.
- Cassius Dio, Roman History, Fragments of Book XII (including text by Zonaras);
- Livius, Periochae, Book 20;
- Livius, Ab Urbe Condita, Book 21.2;
- Polybius, The Histories, Book 2.31-2.36;
- Polybius, The Histories, Book 3.13, 3.15 and 3.30;
- Plutarch, Life of Marcellus.
- Adrian Goldsworthy, The Fall of Carthage, p. 139-140;
- Adrian Goldsworthy, In the Name of Rome, p. 45-47;
- Richard Miles, Carthage must be destroyed, p. 222-225.
 Gaius Julius Caesar was the next person to be given this honour in 44 BCE, although he never defeated an enemy commander in single combat. In 29 BCE, Marcus Licinius Crassus (grandson of the triumvir) personally defeated Deldo, King of the Bastarnae. Technically, this would have given him the privilege to dedicate the spolia opima, but Octavian denied it to him.