Sinn Féin for nine years. (It merged with two other organisations to form Fine Gael in 1933.) Anti-Treaty Sinn Féin members continued to boycott the Dáil. At a special "Ard Fheis" in March 1926, de Valera proposed that elected members be allowed to take their seats in the Dáil if and when the controversial Oath of Allegiance was removed. When his motion was defeated, de Valera resigned from Sinn Féin; on 16 May 1926, he founded his own party, Fianna Fáil, which was dedicated to republicanising the Free State from within its political structures. He took most Sinn Féin TDs with him.
Sinn Féin Bank founding council comprised George W. Russell, Arthur Griffith, and P. T. Daly. In 1910 it purchased headquarters at 6 Harcourt Street for £575, leasing the upper floors to the Sinn Féin party, from where the "Sinn Féin" newspaper was edited. A contemporary wrote, "we do not envy the man who has the job of persuading [nationalists] that the new Sinn Fein bank (which we take it will be established without complying with the requirements of British law) is a secure nest for his savings as the Bank of Ireland". When the First Dáil proclaimed an Irish Republic in 1919, it