‘In the following month (May 8, 1816) Mr. Coleridge offered Mr. Murray
his "Remorse" for publication, with a Preface. He also offered his poem
of "Christabel," still unfinished. For the latter Mr. Murray agreed to
give him seventy guineas, "until the other poems shall be completed,
when the copyright shall revert to the author," and also £20 for
permission to publish the poem entitled "Kubla Khan."…’
Coleridge’s “Christabel” has a controversial connection with Walter Scott, since Scott heard Coleridge recite an early version, in 1802. As related on the Spencerians.cath.vt.edu website, Scott borrowed a line and something of the cadence from Coleridge’s poem in his "Lay of the Last Minstrel". It took until 1816 for Coleridge to reach a conclusion and publish, thanks to publisher John Murray. The text above comes from Samuel Smiles’ “A Publisher and his Friends”.