Ah, checking back I see that Lighter posted the Ironhead Baker Youtube link ten days ago, and commented that this "version seems almost like a missing link between the broadsides and "The Streets of Laredo."

My feelings exactly. And it is a little odd that the first line (transcribed by Lomax as 'It was early one mornin' as I passed St. James Hospital') isn't on the recording. The tune, incidentally, sounds to me very like Texas Gladdens 'The Bad Girl's Lament'.

Thinking some more about the 'St James' business while cycling to the shops, I reckon that the two 'St James Hospital' texts that predate 1920 and were collected as far apart as Virginia and Nova Scotia constitute good evidence - albeit circumstantial - that this line originated in the British Isles. There were well established sea routes across the Atlantic to both North American locations, but it's hard to imagine there was much traffic between the Appalachians and the Canadian Maritimes (1300 miles apart) in the 1910s. If someone knows different, feel free to correct me.