John Keats died at age twenty-five. He wrote at a feverish pace and left behind a body of work distinguished by its genius. His poetry ranks him among the greatest Romantic poets. Keats was deeply influenced by Edmund Spenser’s The Faerie Queene (1590, 1596) and the works of Leigh Hunt. This influence is especially evident in Endymion: A Poetic Romance.

Keats wanted to write a “long poem” that would be a “trial of invention.” The poem became Endymion, an effort of some four thousand lines that he wrote in less than a year, the result of Keats’s self-imposed poetic apprenticeship. In it, he appropriates (and often changes) Greek myth.

Keats was not satisfied with Endymion, aware of the extent and nature of the poem’s shortcomings. In a letter to John Taylor, his publisher, Keats wrote, “I am anxious to get Endymion printed so that I may forget it.” He thought of the poem as an exercise or tool in his growth as a poet. He put forth his negative thoughts on Endymion in the preface to the poem, where he spells out his regret that he made it public: “What manner I mean, will be quite clear to the reader, who must soon perceive great inexperience, immaturity, and every error denoting a feverish attempt, rather than a deed accomplished.” Keats places himself somewhere between the healthy “imagination of a boy” and “mature imagination of a man”—a place where “the soul is in a ferment, the character undecided, the way of life uncertain. . . .” From such ferment derives what Keats called the “mawkishness” of Endymion.

The structure of Endymion follows what Jack Stillinger calls a “spatial conception of two realms in opposition and a mythlike set of actions involving characters shuttling back and forth between them.” In book 1, Endymion and his sister occupy the actual world, although Endymion wants to move up to the realm of the ideal world—a place of higher reality. In books 2, 3, and 4, Endymion journeys on a quest for his dream lover, occupying realms of the fantastic. In book 4, Endymion briefly returns to the actual world but disappears back into the ideal world. The pain-pleasure dichotomy of life is addressed in Endymion—as in most of Keats’s works—with the painful aspect existing in the actual world and the pleasure aspect existing in the idealized world. To make this dichotomy work, Keats, at his best, generally employs character pairings of mortals and immortals.

In Endymion , Keats freely borrows from Greek mythology, using the character of Endymion, a chieftain king, and his passion for the Moon goddess Cynthia (known in Greek mythology as Diana). Keats is very free in his interpretation of Cynthia, generally considered a goddess of chastity, the Moon being out of reach. The “pleasure thermometer” passage, so named from a letter Keats sent to his publisher, Taylor, sets the tone of the poem and allows the introduction of eroticism and sexual imagery. Endymion’s encounters with his dream lover Cynthia occur in dreams, but they are anything but chaste. Instead, they are very erotic; the lovers entwine, pant, sigh, faint, caress—the supposedly chaste Cynthia speaks of melting into Endymion. This eroticism is balanced by sexual imagery in the poem. The love between Adonis and Venus in the Garden of Adonis is presented as a sexual relationship that can never develop or mature. On the other hand, the relationship between Glaucus and Circe symbolizes the destructive nature of mature sexuality. The sexual relationship that Endymion seeks with Cynthia lies somewhere between that of Adonis and Venus and...