Members of the First Dáil - Joseph MacDonagh

Joseph MacDonagh (listed as J. McDonagh): Fourth Row: First on the Left

Joseph MacDonagh (died 25 December 1922) was an Irish Sinn Féin politician. He was also the brother of the executed 1916 Easter Rising leader Thomas MacDonagh.

He was elected unopposed as a Sinn Féin MP for the Tipperary North constituency at the 1918 general election. In January 1919, Sinn Féin MPs refused to recognise the Parliament of the United Kingdom and instead assembled at the Mansion House in Dublin as a revolutionary parliament called Dáil Éireann, though MacDonagh did not attend as he was in prison. He was elected unopposed as a Sinn Féin Teachta Dála (TD) for the Tipperary Mid, North and South constituency at the 1921 elections.

He was Director of the "Belfast Boycott", an attempt in 1920–21 to boycott goods from Ulster that were being imported into the south of Ireland. He opposed the Anglo-Irish Treaty and voted against it. He was re-elected for the same constituency at the 1922 general election, this time as an anti-Treaty Sinn Féin TD, but he did not take his seat in the Dáil. He died on hunger strike on Christmas Day 1922.