Is this it? Recently voted the best song in the world in a BBC World Service poll!
A NATION ONCE AGAIN
(Thomas Davis) 1814-1845
When boyhood fire was in my blood I read of ancient freemen
Of Greece and Rome who bravely stood three hundred men and three men
And then I prayed I yet might see our fetters rent in twain
And Ireland long a province be a Nation Once Again
Chorus
A Nation Once Again
A Nation Once Again
And Ireland long a province be a Nation Once Again
And from that time, through wildest woe that hope has shone a far light;
Nor could love’s brightest summer glow, Outshine that solemn starlight;
It seemed to watch above my head, In forum field and fane,
Its angel voice sang around my bed "A Nation Once Again"
Chorus
It whispered too, that freedom ark and service high and holy,
Would be profaned by feelings dark, and passions vain or lowly;
For freedom comes from God’s right hand and needs a godly train;
And righteous men must make our land " A Nation Once Again"
Chorus
So’ as I grew from boy to man I bent me to that bidding-
The spirit of each selfish plan And cruel passion ridding;
For thus I hope some day to aid – Oh can such hope be vain? -
When my dear country will be made "A Nation Once Again.
Chorus
[OK, just realised this song can't be the one, as it was written long before the Easter Rising]