"Endymion; A Poetic Romance" is a four-book epic poem written by John Keats, one of the most significant Romantic poets of the 19th century. The poem tells the story of Endymion, a young shepherd boy who falls in love with the Moon Goddess, Cynthia. Endymion, in his quest to be reunited with Cynthia, embarks on a journey through different realms of the universe, encountering various mythical creatures and challenges along the way. The poem is known for its rich and vivid descriptions of nature and the cosmos, as well as its exploration of themes such as love, beauty, and the power of imagination. Throughout the poem, Keats draws on Greek mythology and symbolism to explore deeper philosophical and metaphysical themes. The poem is also marked by Keats' characteristic melancholic tone and his fascination with the transience of life and beauty. While "Endymion; A Poetic Romance" was not initially well-received by critics, it has since come to be regarded as a significant work in Keats' oeuvre and as an important contribution to the Romantic literary tradition.

In the Spring of 1817, John Keats, then still a little-known poet, set out to write at least forty lines of poetry every day. The result was Endymion. This retelling of the Greek myth has long been celebrated as one of Keats' breakthrough poems, and though throughout the poem it is clear that some days were filled with inspiration, and others were not, the poem's four books filled with adventure and romance remain a great work of one of the 19th century's greatest poets.

Endymion is a poem by John Keats first published in 1818 by Taylor and Hessey of Fleet Street in London. It begins with the line "A thing of beauty is a joy for ever". Endymion is written in rhyming couplets in iambic pentameter.