One can only surmise the identity and background of the narrator of Poe's poem "The Raven." There is not much to go on within the text of the poem itself. What does come across is that the narrator is a lonely, heartbroken intellectual (a library, a bust of figure from Greek mythology), longing for his lost love, Lenore. A solitary morose figure sitting in his library immersing himself in books about the occult and in thought is suddently interrupted by the introduction of a large, black bird -- the raven. In trying desperately to ascertain the meaning of this peculiar intrusion, and the bird's repeated use of the word "nevermore," the narrator's imagination begins to run away from him and he descends into a state of madness -- a condition very consistent with Poe's attachment to themes centered on various states of insanity.
The fate of the narrator's lost love, Lenore, is not specified, but one can conclude that she has passed away. The narrator's (and Poe's) intense fascination with the occult has lead him to believe that the raven was sent from the underworld or afterlife ("Night's Plutonium Shore; Pluto ruled the underworld in Greek mythology), and that the bird is his connection to Lenore. That the bird's only retort to every entreaty is to say "nevermore" drives the narrator to greater and greater depths of irrationality and anger.