Battle of Fidenae (437 BC)

Dissatisfied with the outcome of the first battle, the Romans appointed Mamercus Aemilius Mamercinus to conduct the war as dictator. He chose Lucius Quinctius L. f. L. n. Cincinnatus as his magister equitum and Titus Quinctius Capitolinus Barbatus and Marcus Fabius Vibulanus as his lieutenant-generals.

News of Mamercinus' appointment caused the enemy to return to the northern shore of the Anio and take up a defensive position in the hills between Fidenae and the river. It was not until the Faliscians came to their aid that they moved back to Fidenae itself, encamping outside the walls.^[2] The dictator crossed the Anio and approached Fidenae,^[2] where a dispute began amongst the defenders. The Fidenates and Veientes favored cautious tactics that would prolong the war, while the Faliscians wanted a decisive battle. Tolumnius took the latter approach, concerned that doing otherwise would make the Faliscians withdraw their support. When Mamercinus arrived, the three armies lined up and waited for him to engage first. The Roman cavalry, led by Quinctius, was the first to advance, followed by the infantry. They met the most resistance from enemy cavalry, led by Tolumnius himself;^[3] when he was unhorsed and killed by Aulus Cornelius Cossus, the enemy began to lose morale. The cavalry was routed, and the Romans advanced into the enemy camp.

Prior to the battle, Tolumnius had sent a detachment around the nearby hills in order to sabotage the Roman camp behind their lines. The camp was successfully defended by the lieutenant-general Marcus Fabius Vibulanus.^[4]

Mamercinus returned to Rome in triumph, during which Cossus was also honored for having slain the Etruscan king. The armour of Tolumnius was placed in the Temple of Jupiter Feretrius, where, according to tradition, Romulus had also dedicated spoils taken from an enemy king.^[5] Fidenae was captured by the dictator Quintus Servilius Priscus Structus Fidenas two years later.^[1]