leeneia,

>I think misery makes more sense than Missouri, because if the singer is from the east (where the Shenandoah River is) and he crosses the Missouri, there are no rivers left where he can ply his trade.<

Why would he he have to ply his trade? What trade? Maybe he is just going West!

"Missouri" is very consistent in the historical evidence for this song. On the other hand, "Shenandoah" only becomes (increasingly) consistent after "outside" commentators begin to make that assumption (and their thoughts become available, in print, to others). While of course "Shenandoah" MAY be absolutely correct, there is far more "dissent" in the evidence on this point to call it into question. Therefore, I personally wouldn't assume Shenandoah River/Valley to be the starting point for the interpretation (i.e. if we're thinking about early versions), and I'd be much more inclined to interpret "Missouri [river]" as indicative of the place.

Besides, people in those days --people in the emerging Black-Popular-Song culture-- were much more concerned with the "great" rivers (Missouri, Ohio, Mississippi) and peppered their songs with them. The steamboats were there, and it's where "stuff" was happening. They were arteries and hubs. Shenandoah...hmm, not so much? Scots-Irish rolling around in some greenery? (I'm being silly.) I don't know, but my sense is that songs of this style were not minted in the boondocks. At least, less likely so! Although soft-toned performances of redheads and pennywhistles help us imagine so :-)
https://www.youtube.com/watch?v=W1EG_4IBzbA

If the "original" word was "misery," that would be fascinating. I've not seen enough evidence of that yet to suspect it though. Will keep an eye open.

One question I think is relevant is: How do we suppose people in the Caribbean got so many different variations on this theme? Do we suppose "the" song originates in the U.S. and some "sailors" (for example) carried it there, for example? I wouldn't say that's not possible. But the relative homogeneity of it in the sailors' shipboard context compared to the diversity in the Caribbean and in non-sailor, mostly Black labor contexts around the Gulf of Mexico makes me inclined not to imagine the "standard" Shenandoah as an item that spread with subsequent transformations but rather that the component bits of this theme had circulated, and that the "standard" is one of several expressions manifesting from that theme.

Below is one of my favorite of these variations. I had the fortune of being on the island this past July; all the singers on this recording are since deceased, but the living nephew of one of the singers remembered the song.

http://research.culturalequity.org/rc-b2/get-audio-detailed-recording.do?recordi