Irish nationalist Arthur Griffith founds Sinn Féin as a political party with the main aim of establishing a dual monarchy in Ireland.

Arthur Joseph Griffith was an Irish writer, newspaper editor and politician who founded the political party Sinn Féin. He led the Irish delegation at the negotiations that produced the 1921 Anglo-Irish Treaty, and served as the president of Dáil Éireann from January 1922 until his death later in August.

Sinn Féin is the name of an Irish political party founded in 1905 by Arthur Griffith. It became a focus for various forms of Irish nationalism, especially Irish republicanism. After the Easter Rising in 1916, it grew in membership, with a reorganisation at its Ard Fheis in 1917. It split in 1922 in response to the Anglo-Irish Treaty which led to the Irish Civil War and saw the origins of Fianna Fáil and Fine Gael, the two parties which have since dominated Irish politics. Another split in the remaining Sinn Féin organisation in the early years of the Troubles in 1970 led to the Sinn Féin of today, which is a republican, left-wing nationalist and socialist party.

A political party is an organization that coordinates candidates to compete in a particular area's elections. It is common for the members of a party to hold similar ideas about politics, and parties may promote specific ideological or policy goals.