Daly is the only son among the ten children born to Edward and Catherine Daly (née O’Mara). He is the younger brother of Kathleen Clarke whose husband, Tom Clarke, an active member of the Irish Republican Brotherhood. Daly’s father, Edward, a Fenian, dies five months before his son’s birth at the age of forty-one. His uncle, John Daly, is a prominent republican who had taken part in the Fenian Rising. It is through John Daly that Clarke meets his future wife.
Daly is educated by the Presentation Sisters at Sexton Street, the Congregation of Christian Brothers at Roxboro Road, and at Leamy’s commercial college. He spends a short time as an apprentice baker in Glasgow before returning to Limerick to work in Spaight’s timber yard. He later moves to Dublin where he eventually takes up a position with a wholesale chemist. He lives in Fairview with Kathleen and Tom Clarke.
Daly joins the membership of the Irish Republican Brotherhood, although the exact date is not known. In November 1913, Daly joins the newly founded Irish Volunteers and soon reaches the rank of captain. He is assiduous in his study of military manuals and the professionalism of his company gains the admiration of senior officers in actions such as the Howth gun-running of 1914. In March 1915, he is promoted to the rank of commandant of the 1st Battalion.
During the Easter Rising of 1916, Daly’s battalion is stationed in the Four Courts and areas to the west and north of the centre of Dublin. His battalion sees the most intense fighting of the rising. He surrenders his battalion on Saturday, April 29 after Patrick Pearse orders the surrender. He is held at Kilmainham Gaol.
Daly is given the same quick sham court-martial at Richmond Barracks as the other leaders of the Rising. In his trial, he claims that he was just following orders. Daly is convicted and is executed by firing squad on May 4, 1916, at the age of 25.
Bray railway station was renamed Bray Daly railway station in his honour in 1966.