Felipa, thank you. I know of the contents of the Mudcat thread and Bruce's page. Some of the information on the latter is often repeated but questionable, overclaiming as fact what is only possible by inference. A song title, for example, as referenced in 'A woman is wooed with few strings', does not give us the identity of a song, as songs may have different lyrical content but the same title ('The Croppy Boy', for instance, of which there are two, 'As I Roved Out', of which there are two), or start with the same words. That manuscript is a century after the English 'Calleno', so cannot claim primacy. Of course, it may be a reference to an earlier song, but we don't know that and, without the lyric, we don't know which song.

Felipa and Emily, thank you so much for your advice on Irish language usage. Much appreciated.

Beachcomber, the earliest known lyric is a broadside registered in 1582, which hasn't survived. The only version of the lyric to survive (the same words? We don't know) is 2 years later, 'A Sonet of a Louer in the praise of his lady. To Calen o Custure me: sung at euerie lines end' in 'A Handefull of pleasant delites by Clement Robinson and divers others', as follows (edited highlights:

When as I view your comly grace, Ca. &c
Your golden haires, your angels face :

Your azured veins much like the skies,
Your siluer teeth, your Christall eies.

As all the Muses for a space :
To sit and heare do giue you place.         

Within my self then can I say :
The night is gone, behold the day :

Behold the star so cleare and bright,
As dimmes the sight of Phœbus light :

And thus amazed as I stand,
Not feeling sense, nor moouing hand.