Battle of Telamon The Battle of Telamon was fought between the Roman Republic and an alliance of Gauls in 225 BC . The Romans , led by the consuls Gaius Atilius Regulus and Lucius Aemilius Papus , defeated the Gauls , thus extending their influence over northern Italy . Background . Mobilization . Rome had been at peace with the tribes of Cisalpine Gaul ( the Po valley in northern Italy ) for many years . Indeed , when a force of Transalpine Gauls had crossed the Alps into Italy in 230 BC , it had been the Boii of Cisalpine Gaul who had repelled them . The Romans had sent an army but found it was not needed . However , when the Romans partitioned the formerly Gallic territory of Picenum in 234 BC , this created resentment among its neighbours , the Boii and Insubres . In 225 BC , the Boii and Insubres paid large sums of money to the Gaesatae , mercenaries from Transalpine Gaul led by Aneroëstes and Concolitanus , to fight with them against Rome . The Romans , alarmed by this Celtic mobilisation , made a treaty giving the Carthaginian general Hasdrubal the Fair unimpeded control of Hispania so they could concentrate on the threat closer to home . The Romans called upon their allies in Italy to supply troops . The consul Lucius Aemilius Papus had four legions of Roman citizens , 22 , 000 men in total , plus 32 , 000 allied troops , which he stationed the majority of his forces at Ariminum . He placed 54 , 000 Sabines and Etruscans on the Etruscan border under the command of a praetor , and sent 40 , 000 Umbrians , Sarsinates , Veneti and Cenomani to attack the home territory of the Boii to distract them from the battle . The other consul , Gaius Atilius Regulus , had an army the same size as that of Papus , but was stationed in Sardinia at the time , and there was a reserve of 21 , 500 citizens and 32 , 000 allies in Rome itself , and two reserve legions in Sicily and Tarentum . Gaulish victory at Faesulae . The Gauls overran Etruria and began to march to Rome . The Romans ' troops stationed on the Etrurian border met them at Clusium , three days ' march from Rome , where both sides made camp . That night the Gauls , leaving their cavalry and their camp fires as a decoy , withdrew to the town of Faesulae ( modern Fiesole ) and built defensive obstacles . In the morning the cavalry followed in full view of the Romans , who , thinking the enemy were retreating , pursued them . The Gauls , with the advantage of position , were victorious after a hard battle . Six thousand Romans died and the rest fell back to a defensible hill . That night Papus arrived and made camp nearby . Aneroëstes persuaded the Gauls to withdraw along the Etruscan coast with their booty , and renew the war later when unencumbered . Papus pursued and harassed their rear but did not risk a pitched battle . The other consul , Regulus , had crossed from Sardinia , landed at Pisa , and was marching towards Rome . His scouts met the Gauls ' advanced foragers head on near Telamon ( modern Talamone ) , in an area called " Campo Regio " . The Battle . Regulus put his troops in fighting order and advanced , attempting to occupy a hill above the road by which the Gauls must pass . The Gauls , unaware of Regulus ' arrival , assumed that Papus had sent some of his cavalry ahead , and sent some of their own cavalry and light infantry against them to contest the hill , but as soon as they knew what they were up against they deployed their infantry facing both front and rear . They placed the Gaesatae and Insubres at the rear against Papus , and the Boii and Taurisci at the front against Regulus , their wings protected by wagons and chariots . A small force guarded the booty on another hill nearby . The battle over the main hill was fierce , and despite Papus sending cavalry to assist , Regulus was killed and his head brought to the Gallic leaders . Eventually , however , the Roman cavalry secured possession of the hill . The Romans advanced from both directions , throwing volleys of javelins , which devastated the vulnerable Gaesatae at the rear , who were fighting naked with small shields . Some rushed wildly at the enemy and were slaughtered . Others withdrew into the body of the army , their retreat causing disorder among their allies . The Roman javelin - throwers withdrew into the ranks , and the infantry advanced in maniples . The Insubres , Boii and Taurisci held their ground tenaciously , but the Roman shields and thrusting short swords were more effective in close combat than the Gallic smaller shields and slashing long swords , and the Romans gained the upper hand . Finally , the Roman cavalry rode down the hill onto the Gauls ' flank . Their infantry was slaughtered and their cavalry put to flight . Around 40 , 000 Gauls were killed and 10 , 000 , including Concolitanus , taken prisoner . Aneroëstes escaped with a small group of followers , who committed suicide with him . Papus conducted a punitive expedition against the Boii , and later used the spoils taken in his triumph . The battle was recorded by some historians to be the last use of the war chariot in continental Europe .