Antaine I was talking (briefly) to Johnny Johnston tonight. He got it from Brian McMahon's son (Gabariel?) and thinks it was written about 30 years ago by " a guy in UCG called Fallon". My guess is that it might well have been Padrig Fallon the poet and playwright who, though he didn't work in UCG, was born and reared in Athenry! Johnny reckons that Brian O Rourke also sings it and is likely to know the story.
Regards