Rhea Silvia, also known as Rea Silvia and sometimes as Ilia, was the mother of Romulus and Remus in Roman mythology. According to Latin poet Ennuis (239—169 BCE), she was the daughter of Aeneas—the Trojan hero who led the survivors of the defeated city of Troy to Italy.
Ennuis recounts that after the death of Aeneas, Ilia had a dream that foretold that Mars, the god of war, would visit her. Aeneas appeared to Ilia in the dream and assured her that, following a period of hardship and suffering after her encounter with Mars, her fortunes would change and would “rise out of a river.” The reference was to the salvation of Romulus and Remus, the twin sons of Ilia and Mars, from the Tiber River in Rome. Servius, who commented on the myth of Aeneas given by Virgil (70—19 BCE) in the Aeneid, confirms that Ennius and Naevius (c. 270—c. 199 BCE) affirmed that Romulus was the founder of Rome and that he was the grandson of Aeneas through his daughter Ilia.
According to Greek biographer Plutarch (c. 46-120 CE), Roman tradition continued to honor Romulus and Remus as the city’s founders, but by the first century BCE there had been a major change within the tradition. In the intervening years, ancient scholars had debated the foundation date of the city of Rome. It was no longer set in the years immediately following the Trojan War, but in the period of the eighth century BCE. To bridge the gap between the end of the war and the city’s foundation, and to accommodate an alternative tradition which stated that the first Romans had come from Alba Longa—a city in the mountainous region outside Rome (and not from
Lavinium where Aeneas had settled)—the ancients invented a long series of Alban kings. These rulers had supposedly descended from Aeneas through his son Ascanius (also known as Iulus). The first of these mythical kings was Silvius (“he of the forest”), whose child was Aeneas Silvius; this Aeneas in turn was the father of Latinus Silvius. The cognomen (last name) of Silvius was borne by successive generations of kings who followed Aeneas Silvius on the Alban throne. The name of Rhea Silvia reflects the feminine form of Silvius.