Coleridge's Kubla Khan: What Happens Next?

Let's take Coleridge at his word, and believe that 'Kubla Khan' was originally going to be a much longer poem. The work's celebrated preface dates composition to 'the summer of the year 1797', in 'a lonely farm house between Porlock and Linton'. Coleridge says he read 'the following sentence, or words of the same substance, in Purchas Pilgrimes':

Here the Khan Kubla commanded a palace to be built, and a stately garden thereunto: and thus ten miles of fertile ground were inclosed with a wall.

Then a sleep, during which he dreamt the 'two to three hundred lines' of a completed poem: a marvellous, wonderful poem, it seems. On waking he began to transcribe this dream-vision only to be interrupted by the most famous interruptor in all world literature, the person from Porlock, after whose ill-timed visit STC found 'to his no small surprise and mortification, that though he still retained some vague and dim recollection of the general purport of the vision, yet, with the exception of some eight or ten scattered lines and images, all the rest had passed away like the images on the surface of a stream into which a stone had been cast'. Boo!

Now this story might be, as some editors have suggested it is, mere chaff. Maybe STC never had a larger poem in mind. But, as I say, let's take Coleridge's word: but for Porlock-person, the 50-line poem would have gone on for another, what: 250 lines? 2500 lines? For a while, at any rate. So what was going to happen to Kubla?

There aren't any clues in Purchas His Pilgrimes as to subsequent events. That book merely describes the arrangement of his palace: 

And of course we can never know for certain the direction STC's poem would have taken, had he written the whole of it. The only real hint in the poem itself is that events are going to take a martial turn: 'And mid this tumult Kubla heard from far/Ancestral voices prophesying war!'

What war? Well, here is an account from The Annual Register (a periodical Coleridge did sometimes read, although I can't prove he read this specific issue of it) in which John Reinhold Forster speculates about certain columnar stones discovered by Jesuits in North America:

Kublai-Khan, one of the successors of Genghiz-khan, after the conquest of the southern part of China, sent ships out, to conquer the kingdom of Japan, or, as they call it, Nipan-gri; but in a terrible storm the whole fleet was cast away, and nothing was ever heard of the men in that fleet. It seems that some of these ships were cast to the shores, opposite the great American lakes, between forty and fifty degrees north latitude, and there probably erected these monuments, and were the ancestors of some nations, who are called Mozemlecks, and have some degree of civilization. Another part of this fleet, it seems, reached the country opposite Mexico, and there founded the Mexican empire, which, according to their own records, as preserved by the Spaniards, and in their painted annals, in Purchas's Pilgrimage, are very recent; so that they can scarcely remember any more than seven princes before Motezuma II, who was reigning when the Spaniards arrived there, 1519, under Fernando Cortez; consequently the first of these princes, supposing each had a reign of thirty-three years and four months, and adding to it .the sixteen years of Motezuma, began to reign in the year 1270, when Kublai-Khan, the conqueror of all China and of Japan, was on the throne, and in whose time happened, I believe, the first abortive expedition to Japan, which I mentioned above, and probably furnished North-America with civilized inhabitants. There is, if I am not mistaken, a great similarity between the figures of the Mexican idols, and those which are usually among the Tartars, who embrace the doctrines and religion of the Dalai-Lama, whose religion Kublai-Khan first; introduced among the Monguls, or Moguls. [‘An Account of Some Vestiges of Cultivation and Antiquity which the French met with in their Attempt to Trace Out the Passage By Land from Canada to the South Sea’, Annual Register (1771), 192]

This was quite a fashionable speculation for a while. Here, from the Critical Review (a journal Coleridge certainly read, and indeed was writing for in the 1790s), is another account of the same idea:

Kublai Khan fitted out a fleet from the Chinese sea, in order to conquer Nipon; and this fleet was scattered by storms ... Kublai-Khan reigned from the year 1259 to 1294 of the Christian æra, when he sent a fleet and army to Nipon (or Japan), for the purpose of conquering that country. The ships composing this fleet, were very much shattered by the storm, and it is probable that some of them may not have been able to get back to Japan and China. About this period there sprung up in America, almost at one and the same time, two great empires (those of Mexico and Peru) which had regular institutes of religion; notions of rank and subordination, were in some measure civilized, were connected with each other by various kinds of association, practised agriculture, and in tho matrimonial state did not allow of polygamy. In Mexico, indeed, they even had a kind of hieroglyphic writing, together with many other marks of cultivation; notwithstanding that both these empires are surrounded on all sides by savage and rude nations very inconsiderable in point of extent, and are besides at a distance from each other. Now all this favours the supposition, that these two colonies came thither by sea, in the twelfth and thirteenth centuries; perhaps they are some of the people that were lost in the expedition to Japan, their ships having been driven by the storm to America. ['Forster's History of Discoveries and Voyages', Critical Review (1786) 334]

Might this have been in Coleridge's mind? A tempest at sea; a war fleet destroyed; a perilous ocean crossing, and a new civilisation being founded. It's suggestive, certainly.

If there's a more serious Coleridgean point here (and I appreciate it's hard to insist there is, given the speculative nature of this sort of thing), then it would be about linking the genesis of Kubla Khan in 1797 to Coleridge's own hopes and anxieties about Pantisocracy. This occupied a very large a portion of STC's energies in the mid 1790s, and although by the end of 1795 the scheme had been downgraded from a settlement in America to a settlement in Wales, and by 1796 it was more or less dead-in-the-water (and never to be revived), still it would be surprising if it didn't work its way through the poet's subconscious and into his work in the years immediately following. In which case, what do we have? Kubla Khan, frittering his life away in his pleasure dome, departs on a perilous journey that eventually leads to the founding of a great new civilisation—in America. Which is to say, Cobler Ridge frittering his life away in his pleasure dome, dreams of departing on a perilous journey that will eventually leads to the founding of a great new civilisation—in America.