The Second Dáil (Irish: An Dara Dáil) is Dáil Éireann as it convenes on August 16, 1921, following the dissolution of the First Dáil. The Second Dáil runs until June 8, 1922.

From 1919 to 1922, Dáil Éireann is the revolutionary parliament of the self-proclaimed Irish Republic. The Second Dáil consists of members elected at the 1921 Irish elections, but with only members of Sinn Féin taking their seats. On January 7, 1922, it ratifies the Anglo-Irish Treaty by 64 votes to 57 which ends the Irish War of Independence and leads to the establishment of the Irish Free State on December 6, 1922.

Since 1919, those elected for Sinn Féin at the 1918 Irish general election had abstained from the House of Commons and established Dáil Éireann as a parliament of a self-declared Irish Republic, with members calling themselves Teachtaí Dála or TDs. In December 1920, in the middle of the Irish War of Independence, the British Government passes the Government of Ireland Act 1920, which enacts partition by establishing two home rule parliaments in separate parts of Ireland. These provisions arise out of discussions held at the Irish Convention held in 1917, from which Sinn Féin abstains. In May 1921 the first elections to the House of Commons of Northern Ireland and the House of Commons of Southern Ireland are held, by means of the single transferable vote. On May 10, 1921, the Dáil passes a resolution that the elections scheduled to take place later in the month in both parts of the country will be “regarded as elections to Dáil Éireann.”

In the elections for Southern Ireland, all seats are uncontested, with Sinn Féin winning 124 of the 128 seats, and Independent Unionists winning the four seats representing the Dublin University. In the 1921 Northern Ireland general election, the Ulster Unionist Party (UUP) wins 40 of the 52 seats, with Sinn Féin and the Nationalist Party winning 6 seats each. Of the six seats won by Sinn Féin in Northern Ireland, five are held by people who had also won seats in Southern Ireland.

The Second Dáil responds favourably to the proposal from King George V on June 22, 1921, for a truce, which becomes effective from noon on July 11, 1921. This is upheld by nearly all of the combatants while the months-long process of arranging a treaty gets under way. The Truce allows the Dáil to meet openly without fear of arrest for the first time since September 1919, when it had been banned and driven underground.

During the Second Dáil the Irish Republic and the British Government of David Lloyd George agree to hold peace negotiations. As President of Dáil Éireann, Éamon de Valera is the highest official in the Republic at this time but is notionally only the head of government. In August 1921, to strengthen his status in the negotiations, the Dáil amends the Dáil Constitution to grant him the title President of the Republic, and he thereby becomes head of state.

On September 14, 1921, the Dáil ratifies the appointment of Arthur Griffith, Michael Collins, Robert Barton, Eamonn Duggan and George Gavan Duffy as envoys plenipotentiary for the peace conference in England. These envoys eventually sign the Anglo-Irish Treaty on December 6. The debate on the Treaty starts on December 14, and continues until January 7, 1922. On that date, the Dáil approves the treaty by 64 in favour to 57 against. As the leader of the anti-Treaty minority, de Valera resigns as President. He allows himself to be nominated again but is defeated on a vote of 60–58. He is succeeded as president by Arthur Griffith. The anti-Treaty deputies continue to attend the Dáil, with de Valera becoming the first Leader of the Opposition in the Dáil.

The ratification specified by the Treaty is by “a meeting summoned for the purpose of the members elected to sit in the House of Commons of Southern Ireland.” The Dáil vote does not fulfil this because four unionists are absent and one Northern Ireland member is present. The requisite approval comes at a separate meeting on January 14, 1922, attended by the unionists and boycotted by anti-Treaty TDs. The meeting also approves a Provisional Government led by Collins, which runs in parallel to Griffith’s Dáil government and with overlapping membership. The Government of Ireland Act 1920 requires the Commons to be summoned by the Lord Lieutenant and its members to take an oath of allegiance to the king, whereas the meeting on January 14 is summoned by Griffith and the members present do not take an oath.

Under the terms of the Treaty, a Constituent Assembly is to be elected to draft a Constitution for the Irish Free State to take effect by December 6, 1922. The assembly is also to serve as a “Provisional Parliament” to hold the Provisional Government responsible. This election is held on June 16, 1922, pursuant to both a resolution by the Second Dáil on May 20 and a proclamation by the Provisional Government on 27 May 27.

The Third Dáil is elected at the general election held on June 16, 1922. This election is required to be held under the Anglo-Irish Treaty signed on December 6, 1921.

(Pictured: Some members of the Second Dáil at the Grosvenor Hotel in London, seated (L to R) Éamon de Valera and Arthur Griffith, National Library of Ireland, NPA-RPH-10)