Ascanius (also called Iulus or Julus) was the legendary son of the Trojan hero Aeneas and, in the dominant Roman tradition, of Creusa daughter of Priam. He flees burning Troy with his father and grandfather Anchises, appears as a youth in Virgil's Aeneid, and becomes king of Lavinium and founder of Alba Longa. Under the name Iulus the Julian clan — including Julius Caesar and Augustus — claimed descent from him and thus from Venus. He is not Ascanius son of Aretaon, the Homeric captain of Phrygian allies from Ascania.
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I.Flight and names
In the standard Greco-Roman narrative, Ascanius is Aeneas's child by Creusa. At Troy's fall Aeneas escapes with Anchises on his shoulders and the boy at his side; Creusa is lost. Dionysius records the rename from Euryleon; Virgil's Iulus makes the Julian family ancestors of Rome's first imperial line, and some genealogies extend the stem to Romulus and Remus.
A wholly different Ascanius — son of Aretaon, brother of Phorcys, leader of Phrygians from far Ascania — fights as a Trojan ally in Homer and Apollodorus. That figure (`ascanius-phrygian`) must never be merged with Aeneas's Dardanian heir.
II.In the Aeneid
Virgil presents Ascanius as a teenager tasting war. During the Italian conflict he shoots Numanus, Turnus's brother-in-law; Apollo blesses him — "thus is the path to the stars" (sic itur ad astra) — then orders the Trojans to keep the boy from further battle. His prayer before the shot, audacibus annue coeptis, later furnished the United States motto Annuit coeptis. The famous episode of Sylvia's stag, which kindles war in Latium, also attaches to his hunt.
Virgil has Aeneas, not Ascanius, kill Mezentius and Lausus; other Roman antiquarians give Ascanius a larger military role after Aeneas's death.
III.Alba Longa and succession
After Aeneas dies, Ascanius rules Lavinium; tradition places the founding of Alba Longa thirty years after Lavinium, with Ascanius as its first king. He leaves Lavinia in charge of Lavinium. Succession is disputed: Silvius is either his younger brother or his son; Dionysius distinguishes a Julus son of Ascanius who contests the Alban throne with Silvius.
Through the Alban kings and the Julian claim, Ascanius becomes a hinge between Trojan myth and Roman dynastic ideology — the boy saved from the flames who begets gods yet to be.