16.4
Romulus also marched out to meet him. But when they were face to face and had surveyed each other, they challenged mutually to single combat before battle, while their armies remained quiet under arms. Romulus, then, after making a vow that if he should conquer and overthrow his adversary, he would carry home the man’s armour and dedicate it in person to Jupiter, not only conquered and overthrew him, but also routed his army in the battle which followed, and took his city as well. To the captured citizens, however, he did no harm beyond ordering them to tear down their dwellings and accompany him to Rome, where, he promised them, they should be citizens on equal terms with the rest.
16.5
Now this, more than anything else, was what gave increase to Rome: she always united and incorporated with herself those whom she conquered. But Romulus, after considering how he might perform his vow in a manner most acceptable to Jupiter and accompany the performance with a spectacle most pleasing to the citizens, cut down a monstrous oak that grew in the camp, hewed it into the shape of a trophy, and fitted and fastened to it the armour of Acron, each piece in its due order.
16.6
Then he himself, girding his raiment about him and wreathing his flowing locks with laurel, set the trophy on his right shoulder, where it was held erect, and began a triumphal march, leading off in a paean of victory which his army sang as it followed under arms, and being received by the citizens with joyful amazement. This procession was the origin and model of all subsequent triumphs, and the trophy was styled a dedication to Jupiter Feretrius, so named from the Roman word ferire, to smite; for Romulus vowed to smite his foe and overthrow him.
