I know the song- and I expect that goes for most people- from the Pogues' album- Rum, Sodomy and the Lash- where it is sung by Cait O'Riordan. It's a real oddity- boozy- but with a melancholy lilt and a sinister undertow; guns come into it and a dog is mysteriously shot. You get the feeling there could be a price to pay for refusing the singer's invitation to "be easy and free when you're drinking with me". His boast of having "acres of land (and) men at command." seems to carry an unspoken threat. Who is he anyway- an IRA godfather?
Well maybe- but there's a longer version- presumably the original- in which he's a stage Irishman on a trip to Liverpool- where he hopes to marry "a neat little maiden"- and there falls in with a bunch of his old drinking buddies. He's flash with the cash but there's no menace to him. Stereotypes abound- the house made of mud, the spuds, the booze. It's racial insult disguised as japery- the Anglo-Irish equivalent of a minstrel song. Wikipedia suggests it started on on the music halls- but doesn't identify the original composer or singer.
Whatever it once was it clearly went a journey- and eventually surfaced in Scotland, shorn of its paddywhackery - and with the speaker having aquired a name- and a Scottish name at that- Jock Stewart. The narrative has gone too and the only element of the original lyric that remains is the chorus. It is now close to being the song Cait sings. What the Pogues have done is re-Irish it- keeping the name Jock Stewart but locating him back where he originally came from, in County Kildare- and having him shoot the dog.
Shooting the dog is a touch of genius. It changes everything.
And that's the folk process. The pebble tumbles and gets bashed about in the stream. In this case the original lyrics were trash, but the tune was too good to throw away. There's been conscious reinvention- helped along, perhaps by Chinese whispers - and the result is this ambiguous and beautiful thing