I have my own version which is based on a translation a friend did of the Irish lyrics.

Last night as I wandered from here,
Far away from the safety of home,
A mystical beauty came near,
To enchant me as never I've known.
I bowed to her beauty and charm,
To words from lips tender and sweet
Her embrace kept me safe from all harms
Is ar Éirinn ní n-eósainn cé h-í.

If she to my words would take heed,
Then the voice of my heart could ring true
To her will I would gladly ascede
Her desirs I would satisfy too
I would read to her stories of old
I would die for this woman with ease
For one kiss my heart would explode
Is ar Éirinn ní n-eósainn cé h-í.

A vision of beauty and grace
resides just beyond my domain
There is beauty and joy in her face
And her reason is honest and plain.
Her hair is as gold when it shines
her cheeks, like th rose, ar aflame
And my heart to her will it resigns
But for Ireland I'd not tell her name.

(trans Sinead Cassidy, adapted Trev Hill)

Here's another version:

http://www.cranfordpub.com/langan/for_ireland.htm