Hi

Looks like Peggy Lettermore. Lettermore or Leitirmór is an island off Galway on the west coast of Ireland. I have pasted links to the site where I found it and also an English language version below.
Anseo

Peggy Lettermore

Tá Peig agom, tá Cáit agom, ach Peig an bean is fearr
'Cbe faer Gheabhfas í nach air a bhfeás anttadh

Ó ghuairm í 's guairim í go deo
Sí grá mo chroí mo bhurnín í sí Peigín Leitirmór

Tá iscaraigh na h'iarrthartha in greim an Ghotán mhoie
Agus scríothim aisteach is gheobhfam leath-bhód sheoil

Ó ghuairm í 's guairim í go deo
Sí grá mo chroí mo bhurnín í sí Peigín Leitirmór

Tá iascaraigh na Gaillimhe ag theacht anall le chóir
Is solas geallaigh gilte bí go ligadis a shaoil

Ó ghuairm í 's guairim í go deo
Sí grá mo chroí mo bhurnín í sí Peigín Leitirmór

Éirigh suas a Pheggy agus sheas ar bharr an árd
Chóirigh do chuid buillán agus féach an bhfuil síad ann

Ó ghuairm í 's guairim í go deo
Sí grá mo chroí mo bhurnín í sí Peigín Leitirmór

Found here

English;
Peggy Lettermore

O welcome and acclaimed is she, my love
Dear to my soul, a thousand told, is Peggy Lettermore

Rise up, dear Peggy and stand up on the height
Count all your cattle and make sure they're all there

O welcome and acclaimed is she, my love
Dear to my soul, a thousand told, is Peggy Lettermore

I have Brid and I have Kate but Peggy is the best of all
Whichever man wins her hand, a lucky man he will be

O welcome and acclaimed is she, my love
Dear to my soul, a thousand told, is Peggy Lettermore

I sent a message west to her, that I would buy a large boat
She sent a message back to me that a medium sized sailing boat would do

O welcome and acclaimed is she, my love
Dear to my soul, a thousand told, is Peggy Lettermore

The Galway fishermen are sailing from the east with a fair wind
With the light of a bright moon in order to see the "jewel"

O welcome and acclaimed is she, my love
Dear to my soul, a thousand told, is Peggy Lettermore

Fergus