The Wolfe Tones, Eire Ogg, Mary Black, Sinead O'Connor (traditionnal, rather than her own songs), The Chieftains, Seanchai, and so many other names I could give!
Names of songs maybe?
The Ballad of Mairead Farrel
The Foggy Dew
Paddy's Lament
Suil A Ruin
He Moved Through the Fair
Erin Go Bragh
Sunday Bloody Sunday (John Lennon, not U2!)
The IRA will set them free
Go on Home British Soldiers
Rifles of the IRA
God Save Ireland
Come out ye Black and Tans
Four Green Fields
My Heart is in Ireland
The Ballad of Joe Mc Donnel
Song for Ireland
I'll Tell me Ma (yes, I like this one
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)
Michael Collins
Ireland Unfree
Only Our Rivers Run Free
James Connolly
Mo Ghile Mear
Irish Ways and Irish Laws
Dirty Old Town
Seven Drunken Nights (some old memory of a completely drunk man singing it over and over in one of my village's pubs)
Padraig Pearse
Bobby Sands MP
Fuck the British Army
and so many others...