Irish War of Independence

Since the 1870s, Irish nationalists in the Irish Parliamentary Party (IPP) had been demanding Home Rule, or self-government, from Britain. Fringe organisations, such as Arthur Griffith's Sinn Féin, instead argued for some form of Irish independence, but they were in a small minority.[11]

The demand for Home Rule was eventually granted by the British Government in 1912,[12] immediately prompting a prolonged crisis within the United Kingdom as Ulster unionists formed an armed organisation – the Ulster Volunteers (UVF) – to resist this measure of devolution, at least in territory they could control. In turn, nationalists formed their own paramilitary organisation, the Irish Volunteers.[13]

The British Parliament passed the Government of Ireland Act 1914, known as the Home Rule Act, on 18 September 1914 with an amending Bill for the partition of Ireland introduced by Ulster Unionist MPs, but the Act's implementation was immediately postponed by the Suspensory Act 1914 due to the outbreak of the First World War in the previous month.[14] The majority of nationalists followed their IPP leaders and John Redmond's call to support Britain and the Allied war effort in Irish regiments of the New British Army, the intention being to ensure the commencement of Home Rule after the war.[15] However, a significant minority of the Irish Volunteers opposed Ireland's involvement in the war. The Volunteer movement split, a majority leaving to form the National Volunteers under Redmond. The remaining Irish Volunteers, under Eoin MacNeill, held that they would maintain their organisation until Home Rule had been granted. Within this Volunteer movement, another faction, led by the separatist Irish Republican Brotherhood, began to prepare for a revolt against British rule in Ireland.[16]

The plan for revolt was realised in the Easter Rising of 1916, in which the Volunteers launched an insurrection whose aim was to end British rule. The insurgents issued the Proclamation of the Irish Republic, proclaiming Ireland's independence as a republic.[17] The Rising, in which over four hundred people died,[18] was almost exclusively confined to Dublin and was put down within a week, but the British response, executing the leaders of the insurrection and arresting thousands of nationalist activists, galvanised support for the separatist Sinn Féin[19] – the party which the republicans first adopted and then took over as well as followers from Countess Markievicz, who was second-in-command of the Irish Citizen Army during the Easter Rising.[20] By now, support for the British war effort was waning, and Irish public opinion was shocked and outraged by some of the actions committed by British troops, particularly the murder of Francis Sheehy-Skeffington and the imposition of wartime martial law.[21]

Result of the 1918 UK general election in Ireland

In April 1918, the British Cabinet, in the face of the crisis caused by the German spring offensive, attempted with a dual policy to simultaneously link the enactment of conscription into Ireland with the implementation of Home Rule, as outlined in the report of the Irish Convention of 8 April 1918. This further alienated Irish nationalists and produced mass demonstrations during the Conscription Crisis of 1918.[22] In the 1918 general election Irish voters showed their disapproval of British policy by giving Sinn Féin 70% (73 seats out of 105,) of Irish seats, 25 of these uncontested.[23] Sinn Féin won 91% of the seats outside of Ulster on 46.9% of votes cast but was in a minority in Ulster, where unionists were in a majority. Sinn Féin pledged not to sit in the UK Parliament at Westminster, but rather to set up an Irish Parliament.[24] This parliament, known as the First Dáil, and its ministry, called the Aireacht, consisting only of Sinn Féin members, met at the Mansion House on 21 January 1919. The Dáil reaffirmed the 1916 Proclamation with the Irish Declaration of Independence,[25] and issued a Message to the Free Nations of the World, which stated that there was an "existing state of war, between Ireland and England". The Irish Volunteers were reconstituted as the "Irish Republican Army" or IRA.[26] The IRA was perceived by some members of Dáil Éireann to have a mandate to wage war on the British Dublin Castle administration.

RIC and British Army personnel near Limerick, c.1920

The heart of British power in Ireland was the Dublin Castle administration, often known to the Irish as "the Castle".[27] The head of the Castle administration was the Lord Lieutenant, to whom a Chief Secretary was responsible, leading—in the words of the British historian Peter Cottrell—to an "administration renowned for its incompetence and inefficiency".[27] Ireland was divided into three military districts. During the course of the war, two British divisions, the 5th and the 6th, were based in Ireland with their respective headquarters in the Curragh and Cork.[27] By July 1921 there were 50,000 British troops based in Ireland; by contrast there were 14,000 soldiers in metropolitan Britain.[28] While the British Army had historically been heavily dependent on Irish recruitment, concern over divided loyalties led to the redeployment from 1919 of all regular Irish regiments to garrisons outside Ireland itself.[29]

The two main police forces in Ireland were the Royal Irish Constabulary (RIC) and the Dublin Metropolitan Police.[30] Of the 17,000 policemen in Ireland, 513 were killed by the IRA between 1919 and 1921 while 682 were wounded.[30] Of the RIC's senior officers, 60% were Irish Protestants and the rest Catholic, while 70% of the rank and file of the RIC were Irish Catholic with the rest Protestant.[30] The RIC was trained for police work, not war, and was woefully ill-prepared to take on counter-insurgency duties.[31] Until March 1920, London regarded the unrest in Ireland as primarily an issue for the police and did not regard it as a war.[32] The purpose of the Army was to back up the police. During the course of the war, about a quarter of Ireland was put under martial law, mostly in Munster; in the rest of the country British authority was not deemed sufficiently threatened to warrant it.[28] During the course of the war, the British created two paramilitary police forces to supplement the work of the RIC, recruited mostly from World War I veterans, namely the Temporary Constables (better known as the "Black and Tans") and the Temporary Cadets or Auxiliary Division (known as the "Auxies").[33]

West Connemara IRA flying column

On 25 November 1913, the Irish Volunteers were formed by Eoin MacNeill in response to the paramilitary Ulster Volunteer Force that had been founded earlier in the year to fight against Home Rule.[34] Also in 1913, the Irish Citizen Army was founded by the trade unionists and socialists James Larkin and James Connolly following a series of violent incidents between trade unionists and the Dublin police in the Dublin lock-out.[35] In June 1914, Nationalist leader John Redmond forced the Volunteers to give his nominees a majority on the ruling committee. When, in September 1914, Redmond encouraged the Volunteers to enlist in the British Army, a faction led by Eoin MacNeill broke with the Redmondites, who became known as the National Volunteers, rather than fight for Britain in the war.[35] Many of the National Volunteers did enlist, and the majority of the men in the 16th (Irish) Division of the British Army had formerly served in the National Volunteers.[36] The Irish Volunteers and the Irish Citizen Army launched the Easter Rising against British rule in 1916, when an Irish Republic was proclaimed. Thereafter they became known as the Irish Republican Army (IRA). Between 1919 and 1921 the IRA claimed to have a total strength of 70,000, but only about 3,000 were actively engaged in fighting against the Crown.[37] The IRA distrusted those Irishmen who had fought in the British Army during the First World War, but there were a number of exceptions such as Emmet Dalton, Tom Barry and Martin Doyle.[37] The basic structure of the IRA was the flying column which could number between 20 and 100 men.[37] Finally, Michael Collins created the "Squad"—gunmen responsible to himself who were assigned special duties such as the assassination of policemen and suspected informers within the IRA.[37]

The years between the Easter Rising of 1916 and the beginning of the War of Independence in 1919 were not bloodless. Thomas Ashe, one of the Volunteer leaders imprisoned for his role in the 1916 rebellion, died on hunger strike, after attempted force-feeding in 1917. In 1918, during disturbances arising out of the anti-conscription campaign, six civilians died in confrontations with the police and British Army and more than 1,000 people were arrested. There were also raids for arms by the Volunteers,[38] at least one shooting of a Royal Irish Constabulary (RIC) policeman and the burning of an RIC barracks in Kerry.[39] The attacks brought a British military presence from the summer of 1918, which only briefly quelled the violence, and an increase in police raids.[40] However, there was as yet no co-ordinated armed campaign against British forces or RIC. In County Cork, four rifles were seized from the Eyeries barracks in March 1918 and men from the barracks were beaten that August.[40] In early July 1918, Volunteers ambushed two RIC men who had been stationed to stop a feis being held on the road between Ballingeary and Ballyvourney in the first armed attack on the RIC since the Easter Rising – one was shot in the neck, the other beaten, and police carbines and ammunition were seized.[40][41] Patrols in Bantry and Ballyvourney were badly beaten in September and October. In November 1918, Armistice Day was marked by severe rioting in Dublin that left over 100 British soldiers injured.[42]

Police wanted poster for Dan Breen, one of those involved in the Soloheadbeg Ambush in 1919.

While it was not clear in the beginning of 1919 that the Dáil ever intended to gain independence by military means, and war was not explicitly threatened in Sinn Féin's 1918 manifesto,[43] an incident occurred on 21 January 1919, the same day as the First Dáil convened. The Soloheadbeg Ambush, in County Tipperary, was led by Seán Treacy, Séumas Robinson, Seán Hogan and Dan Breen acting on their own initiative. The IRA attacked and shot two RIC officers, Constables James McDonnell and Patrick O'Connell,[44] who were escorting explosives. Breen later recalled:

...we took the action deliberately, having thought over the matter and talked it over between us. Treacy had stated to me that the only way of starting a war was to kill someone, and we wanted to start a war, so we intended to kill some of the police whom we looked upon as the foremost and most important branch of the enemy forces. The only regret that we had following the ambush was that there were only two policemen in it, instead of the six we had expected.[45]

This is widely regarded as the beginning of the War of Independence.[46] The British government declared South Tipperary a Special Military Area under the Defence of the Realm Act two days later.[47] The war was not formally declared by the Dáil, and it ran its course parallel to the Dáil's political life. On 10 April 1919 the Dáil was told:

As regards the Republican prisoners, we must always remember that this country is at war with England and so we must in a sense regard them as necessary casualties in the great fight.[48]

In January 1921, two years after the war had started, the Dáil debated "whether it was feasible to accept formally a state of war that was being thrust on them, or not", and decided not to declare war.[49] Then on 11 March, Dáil Éireann President Éamon de Valera called for acceptance of a "state of war with England". The Dail voted unanimously to empower him to declare war whenever he saw fit, but he did not formally do so.[50]

Wall plaque in Great Denmark Street, Dublin where the Dublin IRA Active Service Unit was founded.

Volunteers began to attack British government property, carry out raids for arms and funds and target and kill prominent members of the British administration. The first was Resident Magistrate John C. Milling, who was shot dead in Westport, County Mayo, for having sent Volunteers to prison for unlawful assembly and drilling.[51] They mimicked the successful tactics of the Boers' fast violent raids without uniform. Although some republican leaders, notably Éamon de Valera, favoured classic conventional warfare to legitimise the new republic in the eyes of the world, the more practically experienced Michael Collins and the broader IRA leadership opposed these tactics as they had led to the military débacle of 1916. Others, notably Arthur Griffith, preferred a campaign of civil disobedience rather than armed struggle.[52] The violence used was at first deeply unpopular with Irish people and it took the heavy-handed British response to popularise it among much of the population.[53]

During the early part of the conflict, roughly from 1919 to the middle of 1920, there was a relatively limited amount of violence. Much of the nationalist campaign involved popular mobilisation and the creation of a republican "state within a state" in opposition to British rule. British journalist Robert Lynd wrote in The Daily News in July 1920 that:

So far as the mass of people are concerned, the policy of the day is not active but a passive policy. Their policy is not so much to attack the Government as to ignore it and to build up a new government by its side.[54]

A group of RIC officers in 1917

The IRA's main target throughout the conflict was the mainly Irish Catholic Royal Irish Constabulary (RIC), the British government's armed police force in Ireland, outside Dublin. Its members and barracks (especially the more isolated ones) were vulnerable, and they were a source of much-needed arms. The RIC numbered 9,700 men stationed in 1,500 barracks throughout Ireland.[55]

A policy of ostracism of RIC men was announced by the Dáil on 11 April 1919.[56] This proved successful in demoralising the force as the war went on, as people turned their faces from a force increasingly compromised by association with British government repression.[57] The rate of resignation went up and recruitment in Ireland dropped off dramatically. Often, the RIC were reduced to buying food at gunpoint, as shops and other businesses refused to deal with them. Some RIC men co-operated with the IRA through fear or sympathy, supplying the organisation with valuable information. By contrast with the effectiveness of the widespread public boycott of the police, the military actions carried out by the IRA against the RIC at this time were relatively limited. In 1919, 11 RIC men and 4 Dublin Metropolitan Police G Division detectives were killed and another 20 RIC wounded.[58]

Other aspects of mass participation in the conflict included strikes by organised workers, in opposition to the British presence in Ireland. In Limerick in April 1919, a general strike was called by the Limerick Trades and Labour Council, as a protest against the declaration of a "Special Military Area" under the Defence of the Realm Act, which covered most of Limerick city and a part of the county. Special permits, to be issued by the RIC, would now be required to enter the city. The Trades Council's special Strike Committee controlled the city for fourteen days in an episode that is known as the Limerick Soviet.[59]

Similarly, in May 1920, Dublin dockers refused to handle any war matériel and were soon joined by the Irish Transport and General Workers' Union, who banned railway drivers from carrying members of the British forces. Blackleg train drivers were brought over from England, after drivers refused to carry British troops. The strike badly hampered British troop movements until December 1920, when it was called off.[60] The British government managed to bring the situation to an end, when they threatened to withhold grants from the railway companies, which would have meant that workers would no longer have been paid.[61] Attacks by the IRA also steadily increased, and by early 1920, they were attacking isolated RIC stations in rural areas, causing them to be abandoned as the police retreated to the larger towns.

In early April 1920, 400 abandoned RIC barracks were burned to the ground to prevent them being used again, along with almost one hundred income tax offices. The RIC withdrew from much of the countryside, leaving it in the hands of the IRA.[62] In June–July 1920, assizes failed all across the south and west of Ireland; trials by jury could not be held because jurors would not attend. The collapse of the court system demoralised the RIC and many police resigned or retired. The Irish Republican Police (IRP) was founded between April and June 1920, under the authority of Dáil Éireann and the former IRA Chief of Staff Cathal Brugha to replace the RIC and to enforce the ruling of the Dáil Courts, set up under the Irish Republic. By 1920, the IRP had a presence in 21 of Ireland's 32 counties.[63] The Dáil Courts were generally socially conservative, despite their revolutionary origins, and halted the attempts of some landless farmers at redistribution of land from wealthier landowners to poorer farmers.[64]

The Inland Revenue ceased to operate in most of Ireland. People were instead encouraged to subscribe to Collins' "National Loan", set up to raise funds for the young government and its army.[65] By the end of the year the loan had reached £358,000. It eventually reached £380,000. An even larger amount, totalling over $5 million, was raised in the United States by Irish Americans and sent to Ireland to finance the Republic.[61] Rates were still paid to local councils but nine out of eleven of these were controlled by Sinn Féin, who naturally refused to pass them on to the British government.[64] By mid-1920, the Irish Republic was a reality in the lives of many people, enforcing its own law, maintaining its own armed forces and collecting its own taxes. The British Liberal journal, The Nation, wrote in August 1920 that "the central fact of the present situation in Ireland is that the Irish Republic exists".[54]

The British forces, in trying to re-assert their control over the country, often resorted to arbitrary reprisals against republican activists and the civilian population. An unofficial government policy of reprisals began in September 1919 in Fermoy, County Cork, when 200 British soldiers looted and burned the main businesses of the town, after one of their number – a soldier of the King's Shropshire Light Infantry who was the first British Army death in the campaign – had been killed in an armed raid by the local IRA[66] on a church parade the day before (7 September). The ambushers were a unit of the No 2 Cork Brigade, under command of Liam Lynch, who wounded four of the other soldiers and disarmed the rest before fleeing in their cars. The local coroner's inquest refused to return a murder verdict over the soldier and local businessmen who had sat on the jury were targeted in the reprisal.[67]

Arthur Griffith estimated that in the first 18 months of the conflict, British forces carried out 38,720 raids on private homes, arrested 4,982 suspects, committed 1,604 armed assaults, carried out 102 indiscriminate shootings and burnings in towns and villages, and killed 77 people including women and children.[68] In March 1920, Tomás Mac Curtain, the Sinn Féin Lord Mayor of Cork, was shot dead in front of his wife at his home, by men with blackened faces who were seen returning to the local police barracks. The jury at the inquest into his death returned a verdict of wilful murder against David Lloyd George (the British Prime Minister) and District Inspector Swanzy, among others. Swanzy was later tracked down and killed in Lisburn, County Antrim. This pattern of killings and reprisals escalated in the second half of 1920 and in 1921.[69]

Michael Collins

Michael Collins was a driving force behind the independence movement. Nominally the Minister of Finance in the republic's government and IRA Director of Intelligence, he was involved in providing funds and arms to the IRA units and in the selection of officers. Collins' charisma and organisational capability galvanised many who came in contact with him. He established what proved an effective network of spies among sympathetic members of the Dublin Metropolitan Police's G Division and other important branches of the British administration. The G Division men were a relatively small political division active in subverting the republican movement and were detested by the IRA as often they were used to identify volunteers, who would have been unknown to British soldiers or the later Black and Tans. Collins set up the "Squad", a group of men whose sole duty was to seek out and kill "G-men" and other British spies and agents. Collins' Squad began killing RIC intelligence officers in July 1919.[70] Many G-men were offered a chance to resign or leave Ireland by the IRA. One spy who escaped with his life was F. Digby Hardy, who was exposed by Arthur Griffith before an "IRA" meeting, which in fact consisted of Irish and foreign journalists, and then advised to take the next boat out of Dublin.[71]

The Chief of Staff of the IRA was Richard Mulcahy, who was responsible for organising and directing IRA units around the country. In theory, both Collins and Mulcahy were responsible to Cathal Brugha, the Dáil's Minister of Defence, but, in practice, Brugha had only a supervisory role, recommending or objecting to specific actions. A great deal also depended on IRA leaders in local areas (such as Liam Lynch, Tom Barry, Seán Moylan, Seán Mac Eoin and Ernie O'Malley) who organised guerrilla activity, largely on their own initiative. For most of the conflict, IRA activity was concentrated in Munster and Dublin, with only isolated active IRA units elsewhere, such as in County Roscommon, north County Longford and western County Mayo.

While the paper membership of the IRA, carried over from the Irish Volunteers, was over 100,000 men, Michael Collins estimated that only 15,000 were active in the IRA during the course of the war, with about 3,000 on active service at any time. There were also support organisations Cumann na mBan (the IRA women's group) and Fianna Éireann (youth movement), who carried weapons and intelligence for IRA men and secured food and lodgings for them. The IRA benefitted from the widespread help given to them by the general Irish population, who generally refused to pass information to the RIC and the British military and who often provided "safe houses" and provisions to IRA units "on the run".

Much of the IRA's popularity arose from the excessive reaction of the British forces to IRA activity. When Éamon de Valera returned from the United States, he demanded in the Dáil that the IRA desist from the ambushes and assassinations, which were allowing the British to portray it as a terrorist group and to take on the British forces with conventional military methods. The proposal was immediately dismissed.

A group of "Black and Tans" and Auxiliaries in Dublin, April 1921

The British increased the use of force; reluctant to deploy the regular British Army into the country in greater numbers, they set up two auxiliary police units to reinforce the RIC. The first of these, quickly nicknamed as the Black and Tans, were seven thousand strong and mainly ex-British soldiers demobilised after World War I. Deployed to Ireland in March 1920, most came from English and Scottish cities. While officially they were part of the RIC, in reality they were a paramilitary force. After their deployment in March 1920, they rapidly gained a reputation for drunkenness and poor discipline. The wartime experience of most Black and Tans did not suit them for police duties and their violent behavior antagonised many previously neutral civilians.[72]

In response to and retaliation for IRA actions, in the summer of 1920, the Tans burned and sacked numerous small towns throughout Ireland, including Balbriggan,[73] Trim,[74] Templemore[75] and others.

In July 1920, another quasi-military police body, the Auxiliaries, consisting of 2,215 former British army officers, arrived in Ireland. The Auxiliaries had a reputation just as bad as the Tans for their mistreatment of the civilian population but tended to be more effective and more willing to take on the IRA. The policy of reprisals, which involved public denunciation or denial and private approval, was famously satirised by Lord Hugh Cecil when he said: "It seems to be agreed that there is no such thing as reprisals but they are having a good effect."[76]

On 9 August 1920, the British Parliament passed the Restoration of Order in Ireland Act. It replaced the trial by jury by courts-martial by regulation for those areas where IRA activity was prevalent.[77]

On 10 December 1920, martial law was proclaimed in Counties Cork, Kerry, Limerick and Tipperary in Munster; in January 1921 martial law was extended to the rest of Munster in Counties Clare and Waterford, as well as counties Kilkenny and Wexford in Leinster.[78]

It also suspended all coroners' courts because of the large number of warrants served on members of the British forces and replaced them with "military courts of enquiry".[79] The powers of military courts-martial were extended to cover the whole population and were empowered to use the death penalty and internment without trial; Government payments to local governments in Sinn Féin hands were suspended. This act has been interpreted by historians as a choice by Prime Minister David Lloyd George to put down the rebellion in Ireland rather than negotiate with the republican leadership.[80] As a result, violence escalated steadily from that summer and sharply after November 1920 until July 1921. It was in this period that a mutiny broke out among the Connaught Rangers, stationed in India. Two were killed whilst trying to storm an armoury and one was later executed.[81]

British soldiers and relatives of the victims outside Jervis Street Hospital during the military enquiry into the Bloody Sunday shootings at Croke Park

A number of events dramatically escalated the conflict in late 1920. First the Lord Mayor of Cork, Terence MacSwiney, died on hunger strike in Brixton Prison in London in October, while two other IRA prisoners on hunger strike, Joe Murphy and Michael Fitzgerald, died in Cork Jail.

Sunday, 21 November 1920, was a day of dramatic bloodshed in Dublin that became known as Bloody Sunday. In the early morning, Collins' Squad attempted to wipe out leading British intelligence operatives in the capital, in particular the Cairo Gang, killing 16 men (including two cadets, one alleged informer, and one possible case of mistaken identity) and wounding 5 others. The attacks took place at different places (hotels and lodgings) in Dublin.[82]

In response, RIC men drove in trucks into Croke Park (Dublin's GAA football and hurling ground) during a football match, shooting into the crowd. Fourteen civilians were killed, including one of the players, Michael Hogan, and a further 65 people were wounded.[83] Later that day two republican prisoners, Dick McKee, Peadar Clancy and an unassociated friend, Conor Clune who had been arrested with them, were killed in Dublin Castle. The official account was that the three men were shot "while trying to escape", which was rejected by Irish nationalists, who were certain the men had been tortured then murdered.[84]

On 28 November 1920, one week later, the West Cork unit of the IRA, under Tom Barry, ambushed a patrol of Auxiliaries at Kilmichael, County Cork, killing all but one of the 18-man patrol.

These actions marked a significant escalation of the conflict. In response, the counties of Cork, Kerry, Limerick, and Tipperary – all in the province of Munster – were put under martial law on 10 December under the Restoration of Order in Ireland Act; this was followed on 5 January in the rest of Munster and in counties Kilkenny and Wexford in the province of Leinster.[78] Shortly afterwards, in January 1921, "official reprisals" were sanctioned by the British and they began with the burning of seven houses in Midleton, County Cork.

Aftermath of the burning of Cork by British forces

On 11 December, the centre of Cork City was burnt out by the Black and Tans, who then shot at firefighters trying to tackle the blaze, in reprisal for an IRA ambush in the city on 11 December 1920 which killed one Auxiliary and wounded eleven.[85]

Attempts at a truce in December 1920 were scuppered by Hamar Greenwood, who insisted on a surrender of IRA weapons first.[86]

During the following eight months until the Truce of July 1921, there was a spiralling of the death toll in the conflict, with 1,000 people including the RIC police, army, IRA volunteers and civilians, being killed in the months between January and July 1921 alone.[87] This represents about 70% of the total casualties for the entire three-year conflict. In addition, 4,500 IRA personnel (or suspected sympathisers) were interned in this time.[88] In the middle of this violence, de Valera (as President of Dáil Éireann) acknowledged the state of war with Britain in March 1921.[89]

Between 1 November 1920 and 7 June 1921 twenty-four men were executed by the British.[90] The first IRA volunteer to be executed was Kevin Barry, one of The Forgotten Ten who were buried in unmarked graves in unconsecrated ground inside Mountjoy Prison until 2001.[91] On 1 February, the first execution under martial law of an IRA man took place: Cornelius Murphy, of Millstreet in County Cork, was shot in Cork City. On 28 February, six more were executed, again in Cork.

On 19 March 1921, Tom Barry's 100-strong West Cork IRA unit fought an action against 1,200 British troops – the Crossbarry Ambush. Barry's men narrowly avoided being trapped by converging British columns and inflicted between ten and thirty killed on the British side. Just two days later, on 21 March, the Kerry IRA attacked a train at the Headford junction near Killarney. Twenty British soldiers were killed or injured, as well as two IRA men and three civilians. Most of the actions in the war were on a smaller scale than this, but the IRA did have other significant victories in ambushes, for example at Millstreet in Cork and at Scramogue in Roscommon, also in March 1921 and at Tourmakeady and Carowkennedy in Mayo in May and June. Equally common, however, were failed ambushes, the worst of which, for example at Mourneabbey, Upton and Clonmult in Cork in February 1921, saw six, three, and twelve IRA men killed respectively and more captured. The IRA in Mayo suffered a comparable reverse at Kilmeena, while the Leitrim flying column was almost wiped out at Selton Hill. Fears of informers after such failed ambushes often led to a spate of IRA shootings of informers, real and imagined.

The biggest single loss for the IRA, however, came in Dublin. On 25 May 1921, several hundred IRA men from the Dublin Brigade occupied and burned the Custom House (the centre of local government in Ireland) in Dublin city centre. Symbolically, this was intended to show that British rule in Ireland was untenable. However, from a military point of view, it was a heavy defeat in which five IRA men were killed and over eighty captured.[92] This showed the IRA was not well enough equipped or trained to take on British forces in a conventional manner. However, it did not, as is sometimes claimed, cripple the IRA in Dublin. The Dublin Brigade carried out 107 attacks in the city in May and 93 in June, showing a falloff in activity, but not a dramatic one. However, by July 1921, most IRA units were chronically short of both weapons and ammunition, with over 3,000 prisoners interned.[93] Also, for all their effectiveness at guerrilla warfare, they had, as Richard Mulcahy recalled, "as yet not been able to drive the enemy out of anything but a fairly good sized police barracks".[94]

Still, many military historians have concluded that the IRA fought a largely successful and lethal guerrilla war, which forced the British government to conclude that the IRA could not be defeated militarily.[95] The failure of the British efforts to put down the guerrillas was illustrated by the events of "Black Whitsun" on 13–15 May 1921. A general election for the Parliament of Southern Ireland was held on 13 May. Sinn Féin won 124 of the new parliament's 128 seats unopposed, but its elected members refused to take their seats. Under the terms of the Government of Ireland Act 1920, the Parliament of Southern Ireland was therefore dissolved, and executive and legislative authority over Southern Ireland was effectively transferred to the Lord Lieutenant (assisted by Crown appointees). Over the next two days (14–15 May), the IRA killed fifteen policemen. These events marked the complete failure of the British Coalition Government's Irish policy—both the failure to enforce a settlement without negotiating with Sinn Féin and a failure to defeat the IRA.

By the time of the truce, however, many republican leaders, including Michael Collins, were convinced that if the war went on for much longer, there was a chance that the IRA campaign as it was then organised could be brought to a standstill. Because of this, plans were drawn up to "bring the war to England". The IRA did take the campaign to the streets of Glasgow.[96] It was decided that key economic targets, such as the Liverpool docks, would be bombed. The units charged with these missions would more easily evade capture because England was not under, and British public opinion was unlikely to accept, martial law. These plans were abandoned because of the truce.

Catholic-owned businesses destroyed by loyalists in Lisburn, August 1920.

While the IRA was less active in the north-east than in the south, Ulster unionists saw themselves as besieged by Irish republicans. The January and June 1920 local elections saw Irish nationalists and republicans win control of many northern urban councils, as well as Tyrone and Fermanagh county councils. Derry City had its first Irish nationalist and Catholic mayor.[119]

Fighting broke out in Derry on 18 June 1920 and lasted a week. Catholic homes were attacked in the mainly-Protestant Waterside, and Catholics fled by boat across the Foyle while coming under fire. In the Cityside, Loyalists fired from the Fountain neighbourhood into Catholic streets, while the IRA occupied St Columb's College and returned fire. At least fourteen Catholics and five Protestants were killed in the violence.[120] Eventually, 1,500 British troops were deployed in Derry and imposed a curfew.[121]

On 17 July, British Colonel Gerald Smyth was assassinated by the IRA in Cork. He had told police officers to shoot civilians who did not immediately obey orders.[122] Smyth came from Banbridge, County Down. Loyalists retaliated by attacking many Catholic homes and businesses in Banbridge and expelling Catholics from their jobs, forcing many to flee the town.[123] There were similar attacks in nearby Dromore.[124]

On 21 July, loyalists drove 8,000 "disloyal" co-workers from their jobs in the Belfast shipyards, all of them either Catholics or Protestant labour activists. Some were viciously attacked.[125] This was partly in response to recent IRA actions and partly because of competition over jobs due to high unemployment. It was fuelled by rhetoric from Unionist politicians. In his Twelfth of July speech, Edward Carson had called for loyalists to take matters into their own hands, and had linked republicanism with socialism and the Catholic Church.[126] The expulsions sparked fierce sectarian rioting in Belfast, and British troops fired machine-guns to disperse rioters. Eleven Catholics and eight Protestants were killed and hundreds wounded.[125] Catholic workers were soon driven out of all major Belfast factories. In response, the Dáil approved the 'Belfast Boycott' of Unionist-owned businesses and banks in the city. It was enforced by the IRA, who halted trains and lorries and destroyed goods.[127]

On 22 August, the IRA assassinated RIC Inspector Oswald Swanzy as he left church in Lisburn. Swanzy had been implicated in the killing of Cork Mayor Tomás Mac Curtain. In revenge, loyalists burned and looted hundreds of Catholic businesses and homes in Lisburn, forcing many Catholics to flee (see the Burnings in Lisburn). As a result, Lisburn was the first town to recruit special constables. After some of them were charged with rioting, their colleagues threatened to resign, and they were not prosecuted.[128]

Unionist leader James Craig.

In September, Unionist leader James Craig wrote to the British government demanding that a special constabulary be recruited from the ranks of the Ulster Volunteers. He warned, "Loyalist leaders now feel the situation is so desperate that unless the Government will take immediate action, it may be advisable for them to see what steps can be taken towards a system of organised reprisals against the rebels".[129] The Ulster Special Constabulary (USC) was formed in October and, in the words of historian Michael Hopkinson, "amounted to an officially approved UVF".[130]

The Lord Lieutenant inspecting troops outside Belfast City Hall on the day Northern Ireland's parliament first met.

After a lull in violence in the north, the conflict there intensified again in spring 1921. In February, as reprisal for the shooting of a Special Constable, USC and UVF men burned ten Catholic homes and a priest's house in Rosslea, County Fermanagh.[131] The following month, the IRA attacked the homes of sixteen Special Constables in the Rosslea district, killing three and wounding others.[132]

The 'Act of Partition' came into force on 3 May 1921.[133] That month, James Craig secretly met Éamon de Valera in Dublin. They discussed the possibility of a truce in Ulster and an amnesty for prisoners. Craig proposed a compromise of limited independence for the South and autonomy for the North within the UK. The talks came to nothing and violence in the north continued.[134] Elections to the Northern parliament were held on 24 May, in which Unionists won most seats. Its parliament first met on 7 June and formed a devolved government, headed by Craig. Republican and nationalist members refused to attend. King George V addressed the ceremonial opening of the Northern parliament on 22 June.[133] The next day, a train carrying the king's armed escort, the 10th Royal Hussars, was derailed by an IRA bomb at Adavoyle, County Armagh. Five soldiers and a train guard were killed, as were fifty horses. A civilian bystander was also shot dead by British soldiers.[135]

Loyalists condemned the truce as a 'sell-out' to republicans.[136] On 10 July, a day before the ceasefire was to begin, police launched a raid against republicans in west Belfast. The IRA ambushed them on Raglan Street, killing an officer. This sparked a day of violence known as Belfast's Bloody Sunday. Protestant loyalists attacked Catholic enclaves in west Belfast, burning homes and businesses. This led to sectarian clashes between Protestants and Catholics, and gun battles between police and nationalists. The USC allegedly drove through Catholic enclaves firing indiscriminately.[137] Twenty people were killed or fatally wounded (including twelve Catholics and six Protestants) before the truce began at noon on 11 July.[138] After the truce came into effect on 11 July, the USC was demobilized (July - November 1921). The void left by the demobilized USC was filled by loyalist vigilante groups and a revived UVF.[139]

There were further outbreaks of violence in Belfast after the truce. Twenty people were killed in street fighting and assassinations from 29 August to 1 September 1921 and another thirty were killed from 21 to 25 November. Loyalists had by this time taken to throwing bombs randomly into Catholic streets and the IRA responded by bombing trams carrying Protestant workmen.[140]

Despite the Dáil's acceptance of the Anglo-Irish Treaty in January 1922, which confirmed the future existence of Northern Ireland, there were clashes between the IRA and British forces along the new border from early 1922. In part, this reflected Michael Collins' view that the Treaty was a "stepping stone", rather than a final settlement. That month, Collins became head of the new Irish Provisional Government and the Irish National Army was founded, though the IRA continued to exist.[141]

In January 1922, members of the Monaghan Gaelic football team were arrested by Northern police on their way to a match in Derry. Among them were IRA volunteers with plans to free IRA prisoners from Derry prison. In response, on the night of 7–8 February, IRA units crossed the border and captured almost fifty Special Constables and prominent loyalists in Fermanagh and Tyrone. They were to be held as hostages for the Monaghan prisoners. Several IRA volunteers were also captured during the raids.[142] This operation had been approved by Michael Collins, Richard Mulcahy, Frank Aiken and Eoin O'Duffy.[143] The Northern Ireland authorities responded by sealing-off many cross-border roads.[144]

The months of February and March 1922 saw levels of violence in the north that had not been seen before. Between 11 February and 31 March, 51 Catholics were killed with 115 wounded, with 32 Protestants killed and 86 wounded.[145] On 11 February, IRA volunteers stopped a group of armed Special Constables at Clones railway station, County Monaghan. The USC unit was travelling by train from Belfast to Enniskillen (both in Northern Ireland), but the Provisional Government was unaware British forces would be crossing through its territory. The IRA called on the Specials to surrender for questioning, but one of them shot dead an IRA sergeant. This sparked a firefight in which four Specials were killed and several wounded. Five others were captured.[146] The incident threatened to set off a major confrontation between North and South, and the British government temporarily suspended the withdrawal of British troops from the South. A Border Commission was set up to mediate in any future border disputes, but achieved very little.[147]

A mural in Belfast depicting revenge killings by police in Belfast.

These incidents provoked retaliation attacks by loyalists against Catholics in Belfast, sparking further sectarian clashes. In the three days after the Clones incident, more than 30 people were killed in the city, including four Catholic children and two women who were killed by a loyalist grenade on Weaver Street.[147]

On 18 March, Northern police raided IRA headquarters in Belfast, seizing weapons and lists of IRA volunteers. The Provisional Government condemned this as a breach of the truce.[148] Over the next two weeks, the IRA raided several police barracks in the North, killed several officers and captured fifteen.[148][149]

On 24 March, six Catholics were shot dead by Special Constables who broke into the home of the McMahon family (see McMahon killings). This was in revenge for the IRA killing of two policemen.[150] A week later, six more Catholics were killed by Specials in another revenge attack known as the Arnon Street massacre.[151]

Winston Churchill had arranged a meeting between Collins and James Craig on 21 January and the southern boycott of Belfast goods was lifted but then re-imposed after several weeks. The two leaders had further meetings, but despite a joint declaration that "peace is declared" on 30 March, violence continued.[152]

In May 1922 the IRA launched a Northern Offensive, secretly backed by Michael Collins, head of the Irish Provisional Government. By this time, the IRA was split over the Anglo-Irish Treaty, but both pro and anti-treaty units were involved. Some weaponry sent by the British to arm the National Army were in fact given to IRA units and their weapons sent to the North.[153] However, the offensive was a failure. An IRA Belfast Brigade report in late May concluded that continuing the offensive was "futile and foolish" and would "place the Catholic population at the mercy of the Specials".[154]

On 22 May, after the assassination of West Belfast Unionist MP William Twaddell, the Northern government introduced internment and 350 IRA men were arrested in Belfast, crippling its organisation there.[155] The biggest clash of the IRA offensive was the Battle of Pettigo and Belleek, which ended with British troops using artillery to dislodge around 100 IRA volunteers from the border villages of Pettigo and Belleek, killing three volunteers. This was the last major confrontation between the IRA and British forces during the revolutionary period.[156] The cycle of sectarian violence in Belfast continued. May saw 75 people killed in Belfast and another 30 in June. Several thousand Catholics fled the violence and sought refuge in Glasgow and Dublin.[157] On 17 June, in revenge for the killing of two Catholics by Specials, Frank Aiken's IRA unit shot dead six Protestant civilians in Altnaveigh, south Armagh. Three Specials were also ambushed and killed.[158]

Collins held British Field Marshal Sir Henry Wilson (MP for North Down) responsible for the attacks on Catholics in the north and may have been behind his assassination in June 1922, though who ordered the shooting is unproven.[159] The event helped to trigger the Irish Civil War. Winston Churchill insisted after the killing that Collins take action against the Anti-Treaty IRA, whom he assumed to be responsible.[160] The outbreak of civil war in the South ended the violence in the North, as the war demoralised the northern IRA and diverted the organisation from the issue of partition. The Irish Free State quietly ended Collins' policy of covert armed action in Northern Ireland.

The violence in the north fizzled out by late 1922.[161]

• 1923 – The Shadow of a Gunman, play by Seán O'Casey
• 1929 – The Last September, novel by Elizabeth Bowen
• 1931 – Guests of the Nation, short story by Frank O'Connor
• 1970 – Troubles, novel by J. G. Farrell
• 1979 – The Old Jest, novel by Jennifer Johnston, winner of the Whitbread Award
• 1991 - "Amongst Women", novel by John McGahern
• 2010 – The Soldier's Song, novel by Alan Monaghan

• 1926 – Irish Destiny, silent film
• 1929 – The Informer, part-talkie film
• 1934 – The Key, American Pre-Code film
• 1935 – The Informer, John Ford film
• 1936 – The Dawn, Irish film (also called Dawn Over Ireland)
• 1936 – Ourselves Alone, British film
• 1936 – Beloved Enemy, American drama film
• 1937 – The Plough and the Stars, John Ford film
• 1959 – Shake Hands with the Devil, feature film
• 1975 – Days of Hope, 1916: Joining Up
• 1988 – The Dawning, film, based on Jennifer Johnston's The Old Jest
• 1989 – The Shadow of Béalnabláth (1989) RTÉ TV Documentary by Colm Connolly about the life and death of Michael Collins.
• 1991 – The Treaty
• 1996 – Michael Collins, feature film
• 1999 – The Last September (film)
• 2001 – Rebel Heart, BBC miniseries. The theme music of the same name was composed by Sharon Corr.
• 2002 – An Deichniúr Dearmadta (The Forgotten Ten) a TG4 TV Documentary
• 2006 – The Wind That Shakes the Barley, feature film
• 2014 – A Nightingale Falling, film
• 2019 – Resistance, five-part RTÉ miniseries