The Irish Civil War (Irish: Cogadh Cathartha na hÉireann; 28 June 1922 – 24 May 1923) was a conflict that followed the Irish War of Independence and accompanied the establishment of the Irish Free State, an entity independent from the United Kingdom but within the British Empire.
The civil war was waged between the Provisional Government of Ireland and the Anti-Treaty IRA over the Anglo-Irish Treaty. The Provisional Government (which became the Free State in December 1922) supported the terms of the treaty, while the anti-Treaty opposition saw it as a betrayal of the Irish Republic proclaimed during the Easter Rising of 1916. Many of the combatants had fought together against the British in the Irish Republican Army during the War of Independence and had divided after that conflict ended and the treaty negotiations began.
The Civil War was won by the pro-treaty National Army, who first secured Dublin by early July, then went on the offensive against the anti-Treaty strongholds of the south and west, especially the 'Munster Republic'. All urban centres had been captured by the National Army by late August. The guerrilla phase of the Irish Civil War lasted another 10 months, before the IRA leadership issued a "dump arms" order to all units, effectively ending the conflict. The National Army benefited from substantial quantities of weapons provided by the British government, particularly artillery and armoured cars.
The conflict left Irish society divided and embittered for generations. Today, the three largest political parties in Ireland are direct descendants of the opposing sides in the war: Fine Gael, from the supporters of the pro-Treaty side; Fianna Fáil, the party formed from the bulk of the anti-Treaty republicans by Éamon de Valera; and Sinn Féin, comprising the minority of anti-Treaty republicans who refused to join any partitionist party.
Fallout of the Anglo-Irish Treaty
The Anglo-Irish Treaty was agreed upon to end the 1919–1921 Irish War of Independence between the Irish Republic and the United Kingdom of Great Britain and Ireland. The treaty provided for a self-governing Irish state, having its own army and police. The treaty also allowed Northern Ireland (the six north-eastern counties – Fermanagh, Antrim, Tyrone, Derry, Armagh and Down – where collectively the majority population was of the Protestant religion) to opt out of the new state and return to the United Kingdom – which it did immediately. With the Partition of Ireland a two-year period of communal conflict took place within the newly formed Northern Ireland. Rather than creating the independent republic for which nationalists had fought, the Irish Free State would be a dominion of the British Empire with the British monarch as head of state, in the same manner as Canada and Australia. The British suggested dominion status in secret correspondence even before treaty negotiations began, but Sinn Féin leader Éamon de Valera rejected the dominion. The treaty also stipulated that members of the new Irish Oireachtas (parliament) would have to take the following "Oath of Allegiance":
I... do solemnly swear true faith and allegiance to the Constitution of the Irish Free State as by law established, and that I will be faithful to His Majesty King George V, his heirs and successors by law in virtue of the common citizenship of Ireland with Great Britain and her adherence to and membership of the group of nations forming the British Commonwealth of nations.
This oath was highly objectionable to many Irish Republicans. Furthermore, the partition of Ireland, which had already been decided by the Westminster parliament in the Government of Ireland Act 1920, was effectively confirmed in the Anglo-Irish treaty. The most contentious areas of the Treaty for the IRA were the disestablishment of the Irish Republic declared in 1919, the abandonment of the First Dáil, the status of the Irish Free State as a dominion in the British Commonwealth and the British retention of the strategic Treaty Ports on Ireland's south western and north western coasts which were to remain occupied by the Royal Navy. All these issues were the cause of a split in the IRA and ultimately civil war.
Michael Collins, the Irish finance minister and Irish Republican Brotherhood (IRB) president, argued in the Dáil Éireann that the treaty gave "not the ultimate freedom that all nations aspire and develop, but the freedom to achieve freedom". However, those against the treaty believed that it would never deliver full Irish independence.
Split in the Nationalist movement
The split over the Treaty was deeply personal. Many on both sides had been close friends and comrades during the War of Independence. This made their disagreement all the more bitter. On 6 January 1922, at the Mansion House, Dublin, Austin Stack, Home Affairs minister, showed president de Valera the evening news announcing the signing of the Treaty: de Valera merely glanced at it; when Eamonn Duggan, part of the returning Irish delegation, handed him an envelope confirming it, he pushed it aside. De Valera had held secret discussions with UK Prime Minister David Lloyd George from 14 to 21 July in London. Collins, also part of the delegation, supposed (with others) that these discussions confirmed the earlier correspondence, i.e. no British acceptance of a Republic. De Valera, Stack and Defence minister Cathal Brugha had then all refused to join the delegation to London. Collins wrote that his inclusion as a plenipotentiary was "a trap" of de Valera's which he was forewarned of, argued against, but walked into anyway, "as a soldier obeying his commanding officer." Arthur Griffith, the delegation chairman, had made a similar comment about obeying orders to de Valera himself. Mutual suspicion and confusion pertained; the delegation was unclear about the cabinet's instructions and individually became burdened to the point of breakdown. Collins expected the blame for the compromise within the Treaty and wrote: "Early this morning I signed my death warrant." Notwithstanding this, he was frustrated and at times emotional when de Valera and others refused to support the Treaty and friendships died.
Dáil Éireann (the parliament of the Irish Republic) narrowly passed the Anglo-Irish Treaty by 64 votes to 57 on 7 January 1922. Following the Treaty's ratification, in accordance with article 17 of the Treaty, the British-recognised Provisional Government of the Irish Free State was established. Its authority under the Treaty was to provide a "provisional arrangement for the administration of Southern Ireland during the interval" before the establishment of the Irish Free State. In accordance with the Treaty, the British Government transferred "the powers and machinery requisite for the discharge of its duties". Before the British Government transferred such powers, the members of the Provisional Government each "signified in writing [their] acceptance of [the Treaty]".
Upon the Treaty's ratification, de Valera resigned as President of the Republic and failed to be re-elected by an even closer vote of 60–58. He challenged the right of the Dáil to approve the treaty, saying that its members were breaking their oath to the Irish Republic. Meanwhile, he continued to promote a compromise whereby the new Irish Free State would be in "external association" with the British Commonwealth rather than be a member of it (the inclusion of republics within the Commonwealth of Nations was not formally implemented until 1949).
In early March, de Valera formed the Cumann na Poblachta ('Republican Association') party while remaining a member of Sinn Féin, and commenced a speaking tour of the more republican province of Munster on 17 March 1922. During the tour he made controversial speeches at Carrick on Suir, Lismore, Dungarvan and Waterford, saying at one point, "If the Treaty were accepted, the fight for freedom would still go on, and the Irish people, instead of fighting foreign soldiers, will have to fight the Irish soldiers of an Irish government set up by Irishmen." At Thurles several days later he repeated this imagery, and added that the IRA "would have to wade through the blood of the soldiers of the Irish Government, and perhaps through that of some members of the Irish Government to get their freedom."