Lars Tolumnius, was the most famous king of the wealthy Etruscancity-state of Veii, roughly ten milesnorthwest of Rome, best remembered for instigating a war with Rome that ended in a decisive Roman victory.
Background
Very little is known of Tolumnius outside of his involvement in Roman legend. His family was evidently part of the Veientine aristocracy, and its nomen is found on a number of inscriptions from votive offerings. Tolumius enters history when the Roman colony of Fidenae revolted against the Republic in 438 BC, and allied itself with Veii, giving Tolumnius control of the Fidenate army. The Romans sent four envoys to Fidenae to demand an explanation, but they were murdered by the Fidenates, apparently on the king's orders. A popular story held that Tolumnius had not intended this breach of decorum: supposedly he was playing at dice when the Fidenates asked whether they should kill the ambassadors, and having just rolled fortuitously, the king exclaimed, "excellent!", which the Fidenates interpreted as an order to put the Romans to death. Livy is skeptical of this tradition, disbelieving that Tolumnius would have allowed himself to become so easily distracted on an occasion of such importance. Rather, he suggests, Tolumnius intended the execution of the emissaries to involve the Fidenates in a deed that would make it impossible for them to repair the breach with Rome.
War with Rome
Outraged by Tolumnius' actions, the Roman Senatedeclared war against Veii, and the following year dispatched a consular army under the command of Lucius Sergius, which met Tolumnius and the Fidenates south of the Anio. Sergius won the day despite brutal fighting, and earned the surname Fidenas, but the Roman losses were so high that a state of emergency was declared, and the Senate appointed Mamercus Aemilius Mamercinusdictator to meet the threat posed by Tolumnius' forces. Marshaling his troops, the dictator fortified a position at the confluence of the Anio and the Tiber, and waited for Tolumnius to offer battle. Tolumnius, whose army was reinforced by a contingent from Falerii, was content to let the Romans make the first move, but the men of Falerii were eager for battle, so the king agreed to take the field on the following day. He sent a contingent of Veientes through the hills to attack the Romans from the rear, and the battle commenced. The fighting was fierce, and made especially noteworthy by the actions of the Roman and Etruscan cavalry. The Roman cavalry broke through the Etruscan lines, and began pursuing the soldiers as they fled, while Tolumnius at the head of the Etruscan horse valiantly opposed them in the defense of his soldiers. The outcome of the battle was in doubt until Aulus Cornelius Cossus, one of the military tribunes serving in the cavalry, charged at the king and unhorsed him. Before Tolumnius could rise, Cossus dismounted and forced the king to the ground with his shield, and stabbed him repeatedly with his spear. With the king's death, the Etruscan cavalry abandoned the field, and the battle was decided. In recognition of his victory, the dictator Mamercus was granted a triumph, although the most famous hero of the battle was Cossus, who claimed the spolia opima, stripping the arms and armor from the fallen king, and dedicating them at the temple of Jupiter Feretrius. Meanwhile, four statues were erected on the rostra in the forum, in memory of the murdered ambassadors.
