I don't get the connection with An Poc ar Buile unless it's just that we have two language variants. It is a translation of Níl sé na lá - which has a theme similar to the wild rover - and the English variant seems to have taken on a life of its own as we have varied lyrics. Unlike the Irish language versions, I've only heard the English to one tune as sung by Kevin Mitchell and Cathal McConnell. Kevin often sings the chorus in Irish. The tune is one that is commonly used for Níl sé 'na lá (though oddly not in the recordings I can think of) and I think Alison may have already supplied Mudcat with an abc of the tune???