Joseph Aloysius Sweeney (13 June 1897 – 25 November 1980) was an Irish politician and military commander. He fought in the Easter Rising in the GPO and was a member of the IRA during the war of independence. He later became Chief of Staff of the Irish Army. Background Sweeney was born and raised in Burtonport, a town in The Rosses, a district in the west of County Donegal. He was the son of general merchant John Sweeney and Margaret O'Donnell. He came from an Irish Nationalist family; his father had been jailed during the Land War as well as being a president of the local branch of the Ancient Order of Hibernians and a founder of the Irish Volunteers in Donegal. He received his secondary education at St. Enda's School in Rathfarnham, where Patrick Pearse was Headmaster. Pearse solidified Sweeney's nationalist beliefs, and in 1914 Sweeney joined the Irish Volunteers himself. By September 1914 he was a student in University College Dublin and he had transferred to Pearse's unit in the Dublin Brigade, which styled itself "Pearse's own" and had many former students of Pearse amongst their number. In 1915 Sweeney was sworn into the Irish Republican Brotherhood by Pearse. Easter Rising Sweeney was active during the events of the Easter Rising, where he fought in Dublin's Liberty Hall and later the GPO. Following the surrender of rebel forces, Sweeney was interned in Frongoch internment camp in Wales. By October 1916, he'd been released, whereupon he rejoined the Volunteers and once again resumed his studies at UCD. During the following summers he returned to Donegal and reorganised the Volunteers in that county. Irish revolutionary period In 1918 Sweeney was suffering from influenza and decided to take a break from UCD and return to Donegal. While there he was appointed a commandant of the local Volunteers as well as being elected as a Sinn Féin MP for Donegal West in the 1918 Irish general election, defeating the sitting nationalist Hugh Law. Aged 21, had he taken his seat in the British Commons he would have been the youngest member of the house, however, as per Sinn Féin's abstentionist policy he did not and instead attended the meeting of the First Dáil, the new parliament of Ireland created by the Nationalists. He was the youngest Teachta Dála that day and he remains second youngest ever TD to date. In March 1920