In The Penguin Book of American Folksongs Alan Lomax says merely:

Perhaps the best of all the songs set to the tune that Englishmen know as Villikins and his Dinah, this gold-rush ballad tells the rollicking story of a covered wagon trek to California in the days of forty-nine. Such songs were performed by the professional entertainers who toured the gold camps, and were circulated in the little pocket songs books of that day.

WassaiL! V