Kubla Khan or, A Vision in a Dream: A Fragment is a poem written by Samuel Taylor Coleridge, completed in 1797 and published in 1816. Most modern critics now view Kubla Khan as one of Coleridge’s three great poems, along with The Rime of the Ancient Mariner and Chistabel. The poem is considered one of the most famous examples of Romanticism in English poetry, and is one of the most frequently anthologized poems in the English language.

According to Coleridge’s preface to Kubla Khan, the poem was composed one night after he experienced an opium-influenced dream after reading a work describing Xanadu, the summer palace of the Mongol ruler and Emperor of China Kublai Khan. Upon waking, he set about writing lines of poetry that came to him from the dream until he was interrupted by “a person from Porlock”. The poem could not be completed according to its original 200–300 line plan as the interruption caused him to forget the lines. He left it unpublished and kept it for private readings for his friends until 1816 when, at the prompting of Lord Byron, it was published.

Coleridge claimed to have perceived the entire course of the poem in a dream (possibly an opium-induced haze), but was interrupted by this visitor from Porlock while in the process of writing it. Kubla Khan, only 54 lines long, was never completed. Thus “person from Porlock”, “man from Porlock”, or just “Porlock” are literary allusions to unwanted intruders who disrupt inspired creativity.

A copy of the manuscript is a permanent exhibit at the  British Library in London. See Chateau Xanadu in Western Australia.