The supernatural
"La Belle Dame Sans Merci" deals with supernatural elements. The woman that the knight falls in love with is described as a "faery's child." A faery is a mythical, supernatural being, thus, by describing the woman as a faery's child, Keats brings out the theme of supernatural beings in this poem. Moreover, when the knight describes the time he spent with the woman, he states that she gave him wild food, thereby bringing out the eeriness of this woman.
In the end, the knight finds himself on a cold hillside along with other men who were rapt in the same woman's spell. When they saw the knight, they exclaimed that "La Belle Dame sans Merci / Thee hath in thrall!’. Through the setting and the description of the woman, Keats brings out the supernatural element in this poem.
Erotic Love and Seduction
"La Belle Dame Sans Merci" can also be approached through the tensions between erotic love and seduction, and a ideal, chivalrous partnership. When we first meet the knight, he still has "a lily upon [his] brow," signifying his loyalty the courtly tradition. However, as the color quickly drains from his cheeks, he becomes vulnerable to the woman's charms. With his defenses lowered, he quickly succumbs to his desires. Here, love is immediately associated with sex, fantasy, and the supernatural: they make love in the meadows, ride away on the knight's horse, and then the woman expresses her love for him in her "strange language," suggesting her words are closer to a magical spell than the truth.
Does the knight, weak and weary in the forest, give in so quickly to the woman because of her supernatural charm, or because he longs for a love that falls outside of the strict, courtly restraints? While the poem explores the pleasures of sexual liberation, it ends cautiously. His love for the woman is briefly requited, but the satisfaction is short-lived: she leaves him the way she found him, "alone and palely loitering" among the hillside.
The femme fatale
The theme of the femme fatale was popular among Romantic poets. The femme fatale is a seductive, beautiful woman who charms and ensnares men, leading them into dangerous situations. The poem clearly depicts the theme of the femme fatale as the woman, described as a "faery's child," makes the knight fall deeply in love with her, which later leads to his deterioration. Moreover, in the end of the poem, it is revealed that the speaker was not the only man to be ensnared by this woman. The dialogue spoken by the pale lovers—"La belle dame sans merci, / Thee hath in thrall"—further highlights the theme of the femme fatale.
