Michael Collins(Micheál Ó'Coleáin)
Collins fought and brought down the British adminstration in Ireland. He then negiatiated the Anglo-Irish treaty. His war was based on gathering inteligance, assinations(Collins IRA never once had a bombing campaign). He set up units called Flying Columns which were pivotal in the Tan War. He also formed an assination squad called the 12 Apostles whom assinated agents of the crown.
General Tom Barry
"They said I was ruthless, daring, savage, blood thirsty, even heartless. The clergy called me and my comrades murderers but the British were met with their own weapons. They had gone in the mire to destroy us and our nation and down after them we had to go"Commandant General Tom Barry
Ernesto 'Che' Guevara
Needs no introduction