Just as all the old imaginative works rest, after their kind, on long trains of presuppositions, often entirely unmention’d by themselves, yet supplying the most important bases of them, and without which they could have had no reason for being, so Leaves of Grass

In estimating first-class song, a sufficient Nationality, or, on the other hand, what may be call’d the negative and lack of it, (as in Goethe’s case, it sometimes seems to me,) is often, if not always, the first element. One needs only a little penetration to see, at more or less removes, the material facts of their country and radius, with the coloring of the moods of humanity at the time, and its gloomy or hopeful prospects, behind all poets and each poet, and forming their birthmarks. I know very well that my Leaves could not possibly have emerged or been fashion’d or completed, from any other era than the latter half of the nineteenth century, nor any other land than democratic America, and from the absolute triumph of the National Union arms.