I think it may have gone West in two ways, first it was a shantie or Shanty used on American ships only when sailing home. I have seen references to this at least back to the 1860's and I believe earlier. I have also been told by a gentleman I knew who grew up in N.Y.N.Y. and Gavelston Tx during the last Century ( he went on to his reward back in the early 1980's at the ripe old age of 105,) that the song was known by everyone, if you heard it. That ship was bound for home, a cleaned up version might have been popular as a lot of Sailors jumped ship during the gold rushes in the Old West and they very well could of sung it while doing the back breaking work of mining. Also a Western in the 1960s used it as the theme, which would of given it a strong western identification to a lot of people today. These are logical reasons for the songs somewhat split pesonality today