Sinn Fein

Sinn Fein is an Irish republican and democratic socialist political party in the Republic of Ireland and Northern Ireland. The original organization was founded in 1905 by Arthur Griffith. Its members founded the revolutionary Irish Republic and its parliament, the First Dáil, and many of them were active in the Irish War of Independence, during which the party was associated with the Irish Republican Army (1919–1922). The party split before the Irish Civil War and again in its aftermath, giving rise to the two traditionally dominant parties of Irish politics: Fianna Fáil, and Cumann na nGaedheal (which became Fine Gael). Another split in 1970 at the start of the Troubles led to the modern Sinn Fein party, with the other faction eventually becoming the Workers' Party.

During the Troubles, Sinn Fein was associated with the Provisional Irish Republican Army. After Gerry Adams became party leader in 1983, electoral politics were prioritized. In 1986, the party dropped its abstentionist policy for the Dáil; some members formed Republican Sinn Féin in protest. In the 1990s, Sinn Fein was involved in the Northern Ireland peace process. This led to the Good Friday Agreement and created the Northern Ireland Assembly, and saw Sinn Fein become part of the power-sharing Northern Ireland Executive. In 2006, it co-signed the St Andrews Agreement and agreed to support the Police Service of Northern Ireland. Since 2024, Michelle O'Neill has served as the first Irish nationalist First Minister of Northern Ireland. From 2007 to 2022, Sinn Fein was the second-largest party in the Assembly, after the Democratic Unionist Party (DUP), and its nominees served as Deputy First Minister in the Northern Ireland Executive.