Thanks for that information, Q, though I flinched when I read your that "n word" in that quote.

It seems certain that in the "Old Gray Mare" song, "Wild Goose Nation" wasn't a referent for the Irish Guards. It may not matter what it originally meant for it does seem likely {to me} that in that "Old Gray Mare" song, at least, "Wild Goose Nation" referred to an area where Indians lived to which formerly enslaved Black people would run for santuary.