The post of Leader of Fianna Fáil was officially created in 1926 when Éamon de Valera founded the party. De Valera had previously been leader of Sinn Féin and took the Anti-Treaty side during the Civil War. The new party essentially became a home for dissatisfied Sinn Féin TDs who had become disillusioned with the party's abstentionist policy from Dáil Éireann and wanted to republicanise the Irish Free State from within.