Sean Treacy, an only child, was born in 1895 in Soloheadbeg, Co. Tipperary to Denis Treacy and Bridget Allis. After his father died when he was only four, he and his mother moved from Soloheadbeg to Hollyford, Co. Tipperary where his mother had grown up. They returned to Soloheadbeg when Sean was about 11. Sean was a first cousin of Thomas Treacy (see earlier photos).
From a young age Sean had nationalist leanings, and in his teens joined the Irish Republican Brotherhood (which later evolved into the I.R.A.). In January 1919 Sean took part in the Soloheadbeg ambush which was the first military incident of the War of Independence. He subsequently led attacks against the British in Dublin and in various locations in Munster, but on 14 October 1920 he was shot dead in Dublin by a member of the British forces.
This photo of Sean is taken from page 4 of Desmond Ryan’s book “Sean Treacy and the Third Tipperary Brigade I.R.A.”.