Margaret Pearse defeated at the 1922 general election. She supported those who opposed the Treaty during the Irish Civil War and continued to be a member of Sinn Féin until 1926. In 1926 she left the party conference with Éamon de Valera and became a founder member of Fianna Fáil. She never stood for election again. Her daughter Margaret Mary Pearse also joined Fianna Fáil, and served as a TD from 1933 to 1937 and later served in Seanad Éireann as a Senator from 1938 until her death in 1968. At the launch of "The Irish Press" newspaper Margaret was asked to
Fianna Fáil other members split from Sinn Féin when a motion he proposed—which called for elected members to be allowed to take their seats in Dáil Éireann if and when the controversial Oath of Allegiance was removed—failed to pass at the Sinn Féin Ard Fheis in 1926. The party adopted its name on 2 April of the same year. While Fianna Fáil was also opposed to the Treaty settlement, it rejected abstentionism, instead aiming to republicanise the Irish Free State from within. The party's platform of economic autarky had appeal among the farmers, working-class people and the poor while alienating more affluent