Augustine Mary Moore Stack (7 December 1879 – 27 April 1929) was an Irish republican and politician who served as Minister for Home Affairs from 1921 to 1922.

In 1916, as commandant of the Kerry Brigade of the Irish Volunteers, he made preparations for the landing of arms by Roger Casement.

Imprisoned at HM Prison Dartmoor Stack was in the company of senior leaders of the rebellion: Éamon de Valera, Harry Boland and Thomas Ashe.

Stack was a leader of Irish Republican prisoners and led several hunger strikes (including one at Dundalk Gaol) in resistance to being treated as criminals.

[7] Stack, as part of his role as Minister for Home Affairs, was responsible for the creation and administration of the Dáil Courts.

[12] He was captured on 14 April 1923 and went on hunger strike for forty-one days before being released along with approximately 15,000 Sinn Fein and IRA prisoners in July 1924.

When Éamon de Valera founded Fianna Fáil in 1926, Stack remained with Sinn Féin being re-elected to the Dáil at the June 1927 general election.