Titus Livius (Livy), The History of Rome, Book 4
Benjamin Oliver Foster, Ph.D., Ed.

18. The enemy were of several minds. The Faliscans, chafing under service performed away from home¹ and fairly self-confident, demanded battle: the Veientes and Fidenates anticipated greater success from a prolongation of the war. [2] Tolumnius, though the views of his own followers were more agreeable to him, announced that he would fight on the following day, lest the Faliscans might not tolerate a protracted campaign. [3] The dictator and the Romans were encouraged at the enemy's reluctance; and the next day, on the soldiers threatening that they would at once attack the camp and the city, unless the enemy came to an engagement, both armies marched out in line of battle into the plain between the two camps. [4] The Veientes, having men to spare, dispatched a party round the mountains to assail the camp of the Romans during the engagement. The army of the three nations was so drawn up that the Veientes held the right wing, the Faliscans the left, and the Fidenates formed the centre. [5] The dictator advanced on the right, against the Faliscans, and Quinctius Capitolinus on the left, to meet the Veientes; while the master of the horse, with the cavalry, led the attack on the centre. [6] For a brief moment all was hushed and still; since the Etruscans were resolved not to begin fighting unless they were forced, and the dictator kept looking back to the Citadel of Rome, that the augurs might thence make him a signal, as they had arranged to do, the moment the omens were propitious. [7] As soon as he descried the signal, he first sent his cavalry against the enemy, [p. 319]cheering as they charged; and the infantry followed² with a furious attack. [8] At no point could the Etruscan legions withstand the onset of the Romans; their horse made the chief resistance, and of all their horse by far the bravest was the king himself, who rode against the Romans, as they scattered in every direction for the pursuit, and prolonged the struggle.