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.

After a short spell in South Africa, Griffith founded and edited the Irish nationalist newspaper The United Irishman in 1899.

Griffith was elected as an MP for East Cavan in a by-election in June 1918, and re-elected in the 1918 general election, when Sinn Féin won a huge electoral victory over the Irish Parliamentary Party and, refusing to take their seats at Westminster, set up their own constituent assembly, Dáil Éireann.

Arthur Joseph Griffith was born at 61 Upper Dominick Street, Dublin on 31 March 1871,[2] of distant Welsh lineage.

His father had been a printer on The Nation newspaper — Griffith was one of several employees locked out in the early 1890s due to a dispute with a new owner of the paper.

[8] In 1899, on returning to Dublin, Griffith co-founded the weekly United Irishman newspaper with his associate William Rooney, who died in 1901.

[13] In September 1900, he established an organisation called Cumann na nGaedheal ("Society of the Gaels"), to unite advanced nationalist and separatist groups and clubs.

In 1903, he set up the National Council, to campaign against the visit to Ireland of King Edward VII and his consort Alexandra of Denmark.

In his writings, Griffith declared that the Act of Union of Great Britain and Ireland in 1800 was illegal and that, consequently, the Anglo-Irish dual monarchy that existed under Grattan's Parliament and the so-called Constitution of 1782 were still in effect.

The IRB members argued that the aim of dual monarchism should be replaced by republicanism and that Griffith was excessively inclined to compromise with conservative elements (notably in his pro-employer position during the 1913–1914 Dublin Lockout when he saw the syndicalism of James Larkin as aimed at crippling Irish industry for Great Britain's benefit).

[19] When in 1917, surviving leaders of the rebellion were released from gaol (or escaped) they joined Sinn Féin en masse, using it as a vehicle for the advancement of the republic.

In May 1918, along with Éamon de Valera and 72 other Sinn Féiners, Griffith was arrested on the pretext of involvement in the fictitious German Plot.

and held the seat when Sinn Féin subsequently routed the Irish Parliamentary Party at the 1918 general election with a commitment of abstentionism from the British House of Commons.

During de Valera's absence in the United States (1919–21) Griffith served as Acting President and gave regular press interviews.

[citation needed] In Ireland, a general election was held on 24 May 1921 and Griffith, while still in prison, headed the poll in the contested constituency of Fermanagh and Tyrone, and was returned unopposed for Cavan.

[25] In September 1921, de Valera, President of the Republic, asked Griffith to head the delegation of Irish plenipotentiaries to negotiate with the British government.

Griffith was the member of the treaty delegation most supportive of its eventual outcome, a compromise based on dominion status, rather than a republic.

[28] He was confined to a room in St Vincent's by his doctors, who had observed signs of what they thought might be a subarachnoid haemorrhage, but it was difficult to keep him quiet,[29] and he resumed his daily work in the government building.

Fr John Lee of the Marist Fathers administered extreme unction, and Griffith died as the priest recited the concluding prayer.

[citation needed] The historian Diarmaid Ferriter considers that, though he had founded Sinn Féin, Griffith was 'quickly airbrushed' from Irish history.

"[35][36] In late 1899 The United Irishman published an article by Griffith that stated: "I have in former years often declared that the Three Evil Influences of the century were the Pirate, the Freemason, and the Jew.

"[37] The antisemitism found in the pages of the United Irishman during Griffth's editorial tenure has been credited with shaping various aspects of Joyce's Ulysses, especially in the "Cyclops" episode.

[39][4][40] The United Irishman also published articles by Oliver St. John Gogarty that contained antisemitic sentiments, which were common in the Ireland of the time.

[42][43] In 1909, he wrote a favourable article in Sinn Féin on the Jewish contribution to European civilisation, and in Nationality in 1915, he railed against the Irish Parliamentary Party for saying that Jews should be barred from public office.

[40][41] Griffith's publication 'Scissors and Paste' published three separate articles sympathetic to Jewish victims of Eastern European pogroms and in 1915 his 'Nationality' published a piece which defended English Jew Matthew Nathan - "We do not know of one Nationalist Irishman who objects to Sir Matthew Nathan because of the religion he professes, or who holds the creed that an Irish Jew should be ineligible for any office he was competent to fill in an Irish government".