Rhea Silvia
A Vestal, the mother of Romulus and Remus.
Numitor, the father of Rhea Silvia, ruled Alba Longa, the Latin city according to legend founded by Aeneas on the Alban Hills. By Mars she conceived Romulus and Remus. Later she was called Ilia, the Trojan, from Ilium, Troy, and made the daughter of Aeneas to fit the myth of Trojan origin for the Romans.
From Smith's Dictionary of Greek and Roman Biography and Mythology"Marte e Rea Silvia" by Peter Paul Rubens (1547-1640)
From The Myth of the Birth of the Hero by Otto Rank
The Romulus saga later on underwent manifold transmutations, mutilations, additions, and interpretations. It is best known in the form transmitted by Livy (I, 3 ff.), where we learn something about the antecedents and subsequent fate of the twins:
King Proca bequeaths the royal dignity to his firstborn son, Numitor. But his younger brother, Amulius, pushes him from the throne, and becomes king himself. So that no scion from Numitor's family may arise, as the avenger, he kills the male descendants of his brother. Rhea Silvia, the daughter, he elects as a vestal, and thus deprives her of the hope of progeny, through perpetual virginity as enjoined upon her under the semblance of a most honorable distinction. But the vestal maiden was overcome by violence, and having brought forth twins, she named Mars as the father of her illegitimate offspring, be it from conviction, or because a god appeared more creditable to her as the perpetrator of the crime.
The narrative of the exposure in the Tiber goes on to relate that the floating tub, in which the boys had been exposed, was left on dry land by the receding waters, and that a thirsty wolf, attracted from the neighboring mountains by the children's cries, offered them her teats. The boys are said to have been found by the chief royal herder, supposedly named Faustulus, who took them to the homestead of his wife, Larentia, where they were raised. Some believe that Larentia was called Lupa ("she-wolf") by the herders because she offered her body, and that this was the origin of the wonderful saga.
Grown to manhood, the youths Romulus and Remus protect the herds against the attacks of wild animals and robbers. One day Remus is taken prisoner by the robbers, who accuse him of having stolen Numitor's flocks. But Numitor, to whom he is surrendered for punishment, was touched by his tender age, and when he learned of the twin brothers, he suspected that they might be his exposed grandsons. While he was anxiously pondering the resemblance with the features of his daughter, and the boy's age as corresponding to the time of the exposure, Faustulus arrived with Romulus, and a conspiracy was hatched when the descent of the boys had been learned from the herders. The youths armed themselves for vengeance, while Numitor took up weapons to defend his claim to the throne he had usurped. After Amulius had been assassinated, Numitor was reinstituted as the ruler, and the youths resolved to found a city in the region where they had been exposed and brought up. A furious dispute arose upon the question of which brother was to be the ruler of the newly erected city, for neither twin was favored by the right of primogeniture, and the outcome of the bird oracle was equally doubtful. The saga relates that Remus jumped over the new wall, to deride his twin, and Romulus became so much enraged that he slew his brother. Romulus then usurped the sole mastery, and the city was named Rome after him.
From Fasti By Ovid
You might also ask why that cave is called the Lupercal,
And the reason for giving the day such a name.
Silvia, a Vestal, had given birth to divine children,
At the time when her uncle held the throne.
He ordered the infants taken and drowned in the river:
What was he doing? One of the two was Romulus.
Reluctantly his servants obeyed the sad command
(Though they wept) and took the twins to the appointed place.
It chanced that the Albula, called Tiber from Tiberinus
Drowned in its waves, was swollen with winter rain:
You could see boats drifting where the fora are,
And there in the vale of the Circus Maximus.
When the servants arrived there (since they were
Unable to go further), one of them said:
'How alike they are, how beautiful each of them is!
Yet of the two this one is the more vigorous.
If nobility is seen in the face, unless I'm wrong,
I suspect that there's some god within you-
Yet if some god were the author of your being,
He'd bring you aid at such a perilous time:
Your mother would surely bring help if she could,
Who has borne and lost her children in one day:
Born together, to die together, pass together beneath
The waves!' He finished and set them down.
Both squalled alike: you'd have thought they knew.
From History of the Britons ( historia Brittonum), by Nennius
The Britons were thus called from Brutus: Brutus was the son of Hisicion, Hisicion was the son of Alanus, Alanus was the son of Rhea Silvia, Fhea Silvia was the daughter of Numa Pompilius, Numa was the son of Ascanius, Ascanius of Eneas, Eneas of Anchises, Anchises of Troius, Troius of Dardanus, Dardanus of Flisa, Flisa of Juuin, Juuin of Japheth; but Japheth had seven sons; from the first named Gomer, descended the Galli; from the second, Magog, the Scythi and Gothi; from the third, Madian, the Medi; from the fourth, Juuan, the Greeks; from the fifth, Tubal, arose the Hebrei, Hispani, and Itali; from the sixth, Mosoch, sprung the Cappadoces; and from the seventh, named Tiras, descended the Thraces: these are the sons of Japheth, the son of Noah, the son of Lamech.
From Lives of the Noble Grecians and Romans By Plutarch. Romulus
But the story which is most believed and has the greatest number of vouchers was first published, in its chief particulars, amongst the Greeks by Diocles of Peparethus, whom Fabius Pictor also follows in most points. Here again there are variations, but in general outline it runs thus: the kings of Alba reigned in lineal descent from Aeneas and the succession devolved at length upon two brothers, Numitor and Amulius. Amulius proposed to divide things into two equal shares, and set as equivalent to the kingdom the treasure and gold that were brought from Troy. Numitor chose the kingdom; but Amulius, having the money, and being able to do more with that than Numitor, took his kingdom from him with great ease, and, fearing lest his daughter might have children, made her a Vestal, bound in that condition forever to live a single and maiden life. This lady some call Ilia, others Rhea, and others Silvia; however, not long after, she was, contrary to the established laws of the Vestals, discovered to be with child, and should have suffered the most cruel punishment, had not Antho, the king’s daughter, mediated with her father for her; nevertheless, she was confined, and debarred all company, that she might not be delivered without the king’s knowledge. In time she brought forth two boys, of more than human size and beauty, whom Amulius, becoming yet more alarmed, commanded a servant to take and cast away; this man some call Faustulus, others say Faustulus was the man who brought them up. He put the children, however, in a small trough, and went towards the river with a design to cast them in; but, seeing the waters much swollen and coming violently down, was afraid to go nearer, and, dropping the children near the bank, went away. The river overflowing, the flood at last bore up the trough, and, gently wafting it, landed them on a smooth piece of ground, which they now call Cermanes, formerly Germanus, perhaps from Germani, which signifies brothers.