Endymion is a poem by John Keats originally published in 1818. It opens with the line, "A thing of beauty is a joy for ever." For Keats, several words have important connotative meaning. The notion of a bower signifies that the poem is part of a pastoral genre, set in an idyllic countryside. Sweet dreams contrast for Keats with a waking world that could be harsh and painful. Daffodils are often in poetry of this place and period an emblem of spring, signifying renewal of hope after a long dark winter. The term "tales" suggests folk tales and Romantic medievalism as opposed to modern stories. The general tone of the poem is romantic and melancholic, with beauty contrasted with sorrow and joy with a sense of mortality.

The first major metaphor is that of a thing of beauty being presented as a lovely bower in which the spectator can rest in an idyllic pastoral environment separate from the ugly life of London. It is nature groomed and cultivated to provide a place of ease and relaxation. This is an important theme for Keats in that it portrays beauty as a way to draw the mind and heart away from the cares and stresses of daily life.

Poems and tales are compared to "an endless fountain of immortal drink" nourishing the soul and spirit of the reader.