In contrast to epic heroes like Achilles and Odysseus, Aeneas' journey has a different sort of aim. In Homer's Iliad, Achilles' aim was to achieve immortal glory for himself by killing lots of noteworthy Trojans. In Homer's Odyssey, Odysseus' aim was to return to an already-established home on Ithaca and restore order.
Aeneas, like Achilles, is a hero who exhibits might in battle, but his glory does not have the personal aim that Achilles' does. Aeneas fights for something larger than personal glory, he fights so that he can fulfill the destiny that has been established for him by the gods, namely of founding an "empire without end."
Sometimes, Aeneas gets sidetracked as he attempts to fulfill this mission, as he does in his relationship with Dido (see Aeneid 4). Eventually, though, the gods bring Aeneas back into line and Aeneas travels to the underworld and back to discover what he needs to do to establish a new home for himself and his companions in Italy. Thus, in the underworld (see Aeneid 6), Aeneas learns from his father Anchises what the mission of the Romans will be:
remember, Roman, it is for you to rule the nations with your power,
(that will be your skill) to crown peace with law,
to spare the conquered, and subdue the proud.
(A.S. Kline translation)
he is a man with a mission because of the following reasons:
1)he sacrificed his love with dido for his state, (book 4)
2)his reunion with the Evander supposes that he wanted to build a reconciliatory stat