There are hundreds of Raheens in Ireland! Means "little fort".

I have a recording by Frank O' Donovan (definitely the writer of the song, Brackn), from 1940. Sounds like Ratheen? Anyone got a printed version of the lyrics.

Frank O 'Donovan also wrote "Sitting on the Bridge Below the Town".
He was a songwriter, singer and actor, famed for his role as Batty Brennan in the long running RTE serial, "The Riordans". Anyone got his dates?