The title should really be tune origin but that wasn't in the menu.

I was discussing the Welsh Dance Farewell Marian on the ECeilidh list.
I knew that it was by Gwyn Williams but learnt that Pat Shaw also published a verion. http://ottawaenglishdance.org/playford/doku.php?id=ins_farewell_marian.
And I had also heard that it meant Farewell to the Shore. So was that a tune or song before the dance? Indeed, was it a dance before Gwyn and Pat published versions of it?