Fate and Destiny in the Aeneid

Fate and destiny were central parts of Roman mythology and culture, and consequently literature. Although Fate does seem at times to be a device to advance the plot of the Aeneid or to control the character's actions, fate, because of its place in Roman thought, actually plays a larger role. Fate is included by Virgil in his Aeneid to assert through the narrative that the foundation of Rome was divinely ordered, and that this city was destined to become a great empire.
If not for Fate, Aeneis, as the narrative now stands, would have died in Troy. If not for Fate he would have lived out his days with Dido, Queen of Carthage, never founding the city from which Rome would one day spring. The list goes on; Fate is, undoubtedly, a major mover and shaker in the story of Aeneis.
Fate in the Roman tradition was the course which a person's life was meant to travel; he could not strive from this course, and any attempt to do so always ended in advancing his fate rather than deterring it.
The main purpose of Fate in the Aeneid is to demonstrate that the foundation of Rome was fated and thus divinely mandated. The divine approval and support of Rome which necessarily follows from a fated foundation would have achieved this end. Fate was not really necessary to advance the plot. Fate, as utilized by Virgil, was not unnecessarily employed as simply a means to control the characters' actions, but was used as a culturally legitimized means to demonstrate divine involvement and sponsorship in Rome's foundation, thereby raising it from the common run of cities to the divine.
Fate is the ultimate authority, and the future existence of Rome is fated. Not even the gods can withstand fate, and it appears to be Jupiter's function to ensure that what fate determines comes about to pass. Near the start, Jupiter reassures his daughter, Aeneas' mother Venus, and outlines with a superb assurance the smooth workings of Fate that will lead to the foundation of Rome:

"Daughter, dismiss