Born in Galway City in 1891 to a family from Carraroe, Connemara, his parents were Patrick Flaherty and Catherine Clancy.
Colman O'Flaherty, who was killed in action by enemy shellfire near Véry, France, while serving as a military chaplain in the 1st Infantry Division, American Expeditionary Force during World War I and posthumously awarded the Distinguished Service Cross.
He married Agnes Staunton of Kilcolgan in 1922 and had six children: Patrick (later a Mayor), Michael, Colm, Kathleen, Eva and Tina.
He was a pioneer of the bus transport system in the west of Ireland, obtained contracts for mail routes prior to 1923, ran a cinema and O'Flaherty's Motors Limited.
O'Flaherty was one of the longest-serving public representatives i the town, beginning in 1924 till his death on 19 September 1959.