This first appeared in the Griswold edition of 1850; no earlier
publication is known. It was probably Poe's last composition, and this
story of the knight's quest, its failure, and his gaze turned to "the
Valley of the Shadow," is a fitting finale for the ill-starred poet
(see comment in the Introduction, page xxv).
Eldorado: a fabled city or country abounding in gold and
precious stones, and afterward any place of great wealth. The word is
often used figuratively. In a preface to an early volume of his
poetry, Poe alludes quite incidentally to "the poet's own kingdom--his
El Dorado," and in this sense the metaphor may be accepted here.
Note the varying sense of the recurring rhyme, shadow. In the
first stanza it is simply contrasted with the "sunshine" or happiness
of life, in the second it implies the coming of discouragement and
despair, in the third it is the shadow of death cast before, in the
fourth the Valley of the Shadow of Death.