Éamon de Valera new line. However, a vote to accept the Free State Constitution (contingent on the abolition of the Oath of Allegiance) narrowly failed. Soon afterward, de Valera resigned from Sinn Féin and seriously considered leaving politics. However, one of his colleagues, Seán Lemass, convinced de Valera to found a new republican party. In March 1926, with Lemass, Constance Markievicz and others, de Valera formed a new party, Fianna Fáil ("The Warriors of Destiny"), a party that was to dominate 20th-century Irish politics. While Sinn Féin still held to an abstentionist line, Fianna Fáil was dedicated to republicanising the Free State from
Éamon de Valera the IRA dumped their arms rather than surrender them or continue a now fruitless war, de Valera returned to political methods. In 1924, he was arrested in Newry for "illegally entering Northern Ireland" and held in solitary confinement for a month in Crumlin Road Gaol, Belfast. During this time, de Valera came to believe that abstentionism was not a workable tactic in the long term. He now believed that a better course would be to try to gain power and turn the Free State from a constitutional monarchy into a republic. He tried to convince Sinn Féin to accept this