La Belle Dame sans Merci (French: "The Beautiful Lady Without Mercy") is a ballad written by the English poet John Keats. It exists in two versions, with minor differences between them. The original was written by Keats in 1819. He used the title of a 15th century poem by Alain Chartier, though the plots of the two poems are different. The poem is considered an English classic, stereotypical to other of Keats' works. It avoids simplicity of interpretation despite simplicity of structure. At only a short twelve stanzas, of only four lines each, with a simple ABCB rhyme scheme, the poem is nonetheless full of enigmas, and has been the subject of numerous interpretations.
John Keats was one of the principal poets of the English Romantic movement. During his short life, his work received constant critical attacks from the periodicals of the day, but his posthumous influence on poets such as Alfred Tennyson has been immense. Elaborate word choice and sensual imagery characterize Keats's poetry, including a series of odes that were his masterpieces and which remain among the most popular poems in English literature. Keats's letters, which expound on his aesthetic theory of "negative capability", are among the most celebrated by any writer.