Titus Livius (Livy), The History of Rome, Book 2
Benjamin Oliver Foster, Ph.D., Ed.

14. This peaceful departure of the Etruscan king from Rome is inconsistent with the custom handed down from antiquity even to our own age, [p. 265]among other formalities observed at sales of booty,¹ of proclaiming “the goods of King Porsinna.” [2] Such a practice must either have arisen during the war and have been retained when peace was made, or else have had its origin in some kindlier circumstance than would be suggested by the notice that an enemy's goods were to be sold. [3] The most credible of the traditional explanations is that when Porsinna retired from Janiculum he handed over his camp, well stocked with provisions brought in from the neighbouring fertile fields of Etruria, as a gift to the Romans, who were then in a destitute condition after the long siege. [4] These supplies were then sold, lest, if people were given a free hand, they might plunder the camp like an enemy; and they were called the goods of Porsinna rather by way of implying thankfulness for the gift than an auction of the king's property, which was not even in the possession of the Roman People.

[5] On relinquishing his campaign against the Romans, Porsinna was unwilling that he should appear to have led his army into that region to no purpose, and accordingly sent a part of his forces, under his son Arruns, to besiege Aricia. At first the Aricini were paralysed with surprise. [6] Afterwards the auxiliaries whom they called in from the Latin peoples, and also from Cumae, so encouraged them that they ventured to measure their strength with the enemy in the open field. When the battle began, the attack of the Etruscans was so impetuous that they routed the Aricini at the first charge. [7] The Cumaean levies, employing skill to meet force, swerved a little to one side, and when the enemy had swept by them, faced about and attacked them in the rear, with the [p. 267]result that the Etruscans, caught between two lines,² almost in the moment of victory, were cut to pieces. [8] A very small number of them, having lost their leader and finding no nearer refuge, drifted to Rome, unarmed and with all the helplessness and the dejected aspect of suppliants. There they were kindly received and were quartered about among the citizens. [9] When their wounds had healed, some departed for their homes to report the hospitality and kindness they had met with, but many were persuaded to remain in Rome by the affection they felt for their hosts and for the City. To these a place of residence was allotted which was afterwards called the Vicus Tuscus.