In "The Philosophy of Composition" Poe tells the "story" of writing "The Raven." He said among other things that a poem shouldn't be more than 100 lines long, should strive for a sublime tone expressive of Beauty (the subject of prose is "Truth"). He talks of tone telling us that he discovered the effect of repeating the sound "nevermore" in each of the stanzas created an especially mournful tone. And finally, about his quest of the most perfect poem, he says the following:
Now, never losing sight of the object supremeness, or perfection, at all points, I asked myself -- "Of all melancholy topics, what according to the universal understanding of mankind, is the most melancholy?" Death -- was the obvious reply. "And when," I said, "is this most melancholy of topics most poetical?" From what I have already explained at some length, the answer, here also, is obvious -- "Then it most closely allies itself to Beauty: the death, then, of a beautiful woman is, unquestionably, the most poetical topic in the world -- and equally is it beyond doubt that the lips best suited for such topic are those of a bereaved lover."