Titus Livius (Livy), The History of Rome, Book 1
D. Spillan, A.M., M.D., Ed.

3. Ascanius, the son of Aeneas, was not yet old enough to take the government upon him; that government, however, remained secure for him till the age of maturity. [2] In the interim, the Latin state and the kingdom of his grandfather [p. 7]and father was secured for the boy under the regency of his mother (such capacity was there in Lavinia). I have some doubts (for who can state as certain a matter of such antiquity) whether this was the Ascanius, or one older than he, born of Creusa before the fall of Troy, and the companion of his father in his flight from thence, the same whom, being called Iulus, the Julian family call the author of their name. [3] This Ascanius, wheresoever and of whatever mother born, (it is at least certain that he was the son of Aeneas,) Lavinium being overstocked with inhabitants, left that flourishing and, considering these times, wealthy city to his mother or stepmother, and built for himself a new one at the foot of Mount Alba, which, being extended on the ridge of a hill, was, from its situation, called Longa Alba. [4] Between the founding of Lavinium and the transplanting this colony to Longa Alba, about thirty years intervened. Yet its power had increased to such a degree, especially after the defeat of the Etrurians, that not even upon the death of Aeneas, nor after that, during the regency of Lavinia, and the first essays of the young [5??] prince's reign, did Mezentius, the Etrurians, or any other of its neighbours dare to take up arms against it. [6] A peace had been concluded between the two nations on these terms, that the river Albula, now called Tiber, should be the common boundary between the Etrurians and Latins. [7] After him Sylvius, the son of Ascanius, born by some accident in a wood, ascends the throne. He was the father of Aeneas Sylvius, who afterwards begot Latinus Sylvius. [8] By him several colonies, called the ancient Latins, were transplanted. From this time, all the princes, who reigned at Alba, had the surname of Sylvius. From Latinus sprung Alba; from Alba, Atys; from Atys, Capys; from Capys, Capetus; from Capetus, Tiberinus, who, being drowned in crossing the river Albula, gave it a name famous with posterity. [9] Then Agrippa, the son of Tiberinus; after Agrippa, Romulus Silvius ascends the throne, in succession to his father. The latter, having been killed by a thunderbolt, left the kingdom to Aventinus, who being buried on that hill, which is now part of the city of Rome, gave his name to it. [10] After him reigns Proca; he begets Numitor and Amulius. To Numitor, his eldest son, he bequeaths the ancient kingdom of the Sylvian family. [11] But force prevailed [p. 8]more than the father's will or the respect due to seniority: for Amulius, having expelled his brother, seizes the kingdom; he adds crime to crime, murders his brother's male issue; and under pretence of doing his brother's daughter, Rhea Sylvia, honour, having made her a vestal virgin, by obliging her to perpetual virginity he deprives her of all hopes of issue.