It is actually the Gaelic "Dawning of The Day" ie. 'Fáinne Geal an Lae'

A recording by the Cassidys (Na Casaidigh) can be found here;

http://www.youtube.com/watch?v=y0Z4iMRKBc4

English lyrics:

One morning early I went out
On the shore of Lough Leinn
The leafy trees of summertime,
And the warm rays of the sun,
As I wandered through the townlands,
And the luscious grassy plains,
Who should I meet but a beautiful maid,
At the dawning of the day.

No cap or cloak this maiden wore
Her neck and feet were bare
Down to the grass in ringlets fell
Her glossy golden hair
A milking pail was in her hand
She was lovely, young and gay
Her beauty excelled even Helen of Troy
At the dawning of the day.

On a mossy bank I sat me down
With the maiden by my side
With gentle words I courted her
And asked her to be my bride
She turned and said, "Please go away,"
Then went on down the way
And the morning light was shining bright
At the dawning of the day.

CC