Amhrán na bhFiann, also called The Soldier's Song in English, is Ireland's national anthem. The song has three verses, but only the choral refrain is used as the anthem.

Composed the winter 1909/10 by Patrick Heeney, and with lyrics by Peadar Kearney, it was used as marching song by the Irish Volunteers. It was sung by rebels in the General Post Office during the Easter Rising of 1916, and its popularity increased among rebels held in Frongoch internment camp after the Rising. The tune remained popular as an Army tune after the Irish War of Independence, and the Irish Civil War, and soon it was de facto widely adopted as the Irish Anthem. The official adoption came later due to song's history, and the political situation after the Civil War.

Learn more at Wikipedia

Soldiers are we,
whose lives are pledged to Ireland,
Some have come
from a land beyond the wave,
Sworn to be free,
no more our ancient sireland,
Shall shelter the despot or the slave.
Tonight we man the "bearna baoil",
In Erin’s cause, come woe or weal,
’Mid cannon’s roar and rifles’ peal,
We’ll chant a soldier's song

We’ll sing a song, a soldier’s song
With cheering rousing chorus
As round our blazing fires we throng
The starry heavens o’er us
Impatient for the coming fight
And as we await the morning’s light
Here in the silence of the night
We’ll chant a soldier’s song

Soldiers are we...

In valley green, on towering crag
Our fathers fought before us
And conquered ’neath the same old flag
That’s proudly floating o’er us
We’re children of a fighting race
That never yet has known disgrace
And as we march, the foe to face
We’ll chant a soldier’s song

Soldiers are we...

Sons of the Gael! Men of the Pale!
The long-watched day is breaking
The serried ranks of Inisfail
Shall set the tyrant quaking
Our camp fires now are burning low
See in the east a silv’ry glow
Out yonder waits the Saxon foe
So chant a soldier’s song

Soldiers are we...