Plutarch, Romulus
Bernadotte Perrin, Ed.

25. The Roman state thus gathering strength, its weaker neighbours submitted to it, and were satisfied to be let alone; but the powerful ones, out of fear and jealousy, thought they ought not to tolerate, but resist and check the growing power of Romulus. And of the Tuscans, the people of Veii, who possessed much territory and dwelt in a great city, were the first to begin war¹ with a demand for Fidenae, which they said belonged to them. [2] Now this was not only unjust, it was actually ridiculous, that they, who had not come to the aid of the people of Fidenae when they were in the perils of war, but suffered them to perish, then demanded their houses and land from those who had come into possession of them. Accordingly, Romulus gave them contemptuous answers, upon which they divided themselves into two armies, attacked Fidenae with one, and confronted Romulus with the other. Before Fidenae, then, they overpowered two thousand Romans and slew them; but they were defeated by Romulus with a loss of eight thousand men. [3] Once more a battle was fought near Fidenae, and here all agree that the victory was chiefly due to Romulus himself, who displayed every possible combination of skill and bravery, and seemed endowed with strength and swiftness far beyond the lot of man. But there is a statement made by some writers which is altogether fabulous, nay rather, wholly incredible, namely, that of the fourteen thousand Tuscans who fell in this battle, more than half were slain by Romulus with his own hand; for even the Messenians seem to have been boastfully extravagant in saying that Aristomenes thrice offered sacrifice for a hundred Lacedaemonian enemies slain.

[4] After the rout of the enemy, Romulus suffered the survivors to escape, and moved upon their city itself. But they could not hold out after so great a reverse, and suing for peace, made a treaty of friendship for a hundred years, giving up a large portion of their territory, called Septempagium, or the Seven Districts, abandoning their salt-works along the river, and delivering up fifty of their chief men as hostages. [5] Romulus also celebrated a triumph for this victory on the Ides of October, having in his train, besides many other captives, the leader of the Veientes, an elderly man, who seems to have conducted the campaign unwisely, and without the experience to be expected of his years. Wherefore to this very day, in offering a sacrifice for victory, they lead an old man through the forum to the Capitol, wearing a boy's toga with a bulla attached to it, while the herald cries: ‘Sardians for sale!’ For the Tuscans are said to be colonists from Sardis, and Veii is a Tuscan city.