[7][8][9][10] The Provisional IRA emerged from a split in the Irish Republican Army in 1969, partly as a result of that organisation's perceived failure to defend Catholic neighbourhoods from attack in the 1969 Northern Ireland riots.

[18] In the early 1970s, the IRA imported large quantities of modern weapons and explosives, primarily from supporters in the Republic of Ireland and Irish diaspora communities within the Anglosphere as well as the government of Libya.

[21] As the conflict escalated in the early 1970s, the numbers recruited by the IRA mushroomed, in response to the nationalist community's anger at events such as the introduction of internment without trial and Bloody Sunday, when the 1st Battalion, Parachute Regiment of the British Army shot dead 14 unarmed civil rights marchers in Derry.

In July 1972, Provisional leaders Seán Mac Stíofáin, Dáithí Ó Conaill, Ivor Bell, Seamus Twomey, Gerry Adams and Martin McGuinness met a British delegation led by William Whitelaw.

In addition, RUC Chief Constable Kenneth Newman took advantage of Emergency Powers legislation to subject suspected IRA members to "intensive and frequently rough" seven-day interrogations.

They also embarked on a strategy known as the "Long War" – a process of attrition based on the indefinite continuation of an armed campaign until the British government grew tired of the political, military and financial costs involved in staying in Northern Ireland.

[26] The highest military death toll from an IRA attack came on 27 August 1979, with the Warrenpoint ambush in County Down, when 18 British soldiers from the Parachute Regiment were killed by two culvert bombs placed by the South Armagh Brigade, a unit that didn't feel the need to adopt the cell structure because of its history of successfully avoiding intelligence failures.

On the same day, the IRA killed one of their most famous victims, The Earl Mountbatten of Burma, assassinated along with two teenagers (aged 14 and 15) and The Dowager Lady Brabourne in County Sligo, by a bomb placed in his boat.

[49] In late 1976, the IRA leadership met with representatives of the loyalist paramilitary groups and agreed to halt random sectarian killings and car bombings of civilian targets.

However, the authors note that this same belief could also blind them to the actual effects of their campaign, as they did not acknowledge that Northern Irish Unionists regarded themselves as a distinct community and thus would perceive the IRA's activities as sectarian.

[56] James Dingley argues that the IRA's focus on the idea of a united and independent Ireland made it de facto sectarian, as it did not recognise Ulster Unionists as a legitimate group and wanted to use violence to pursue goals that were opposed by the majority of the Northern Irish population.

[57] Protestants in the rural border areas of counties Fermanagh and Tyrone, where the number of members of the security forces killed was high, viewed the IRA's campaign as ethnic cleansing.

Boyle and Hadden argue that the allegations do not stand up to serious scrutiny,[59] while nationalists object to the term on the grounds that it is not used by unionists to describe similar killings or expulsions of Catholics in areas where they form a minority.

[58][62] Gerry Adams, in a 1988 interview, claimed it was, "vastly preferable" to target the regular British Army as it "removes the worst of the agony from Ireland" and "diffuses the sectarian aspects of the conflict because loyalists do not see it as an attack on their community".

[85][86] As well as damaging the tourist industry, the IRA hoped to take advantage of police resources being stretched and launch an assassination campaign against political and military targets including General Frank Kitson.

[84] He met with an IRA member at Carlisle railway station, and they were followed to Glasgow, where they were arrested on 24 June 1985 at a safe house along with three other people, including Martina Anderson and Gerry McDonnell, who had escaped from the Maze Prison in 1983.

[87][88] On several more occasions, the Provisional IRA attacked British troops stationed in England, the most lethal of which was the Deal barracks bombing, in which 11 Royal Marines Band Service bandsmen were killed in 1989.

[98] It has been argued that this bombing campaign convinced the British government (who had hoped to contain the conflict to Northern Ireland with its Ulsterisation policy) to negotiate with Sinn Féin after the IRA ceasefires of August 1994 and July 1997.

"[105] The IRA also sent members on arms importation, logistical support and intelligence operations at different times to continental Europe, Canada, the United States, Australia, Africa, Western Asia and Latin America.

According to author Ed Moloney, the IRA Army Council had plans for a dramatic escalation of the conflict in the late 1980s, which they likened to the Tet Offensive of the Vietnam War, with the aid of the arms obtained from Libya.

[139] Another high-profile incident took place in Gibraltar in March 1988, when three unarmed IRA members were shot dead by an SAS unit while scouting out a bombing target (see Operation Flavius).

[147][148] According to recently released documents, British military intelligence stated in a secret 1973 draft report that within the Ulster Defence Regiment (UDR) it was likely there were soldiers who were also loyalist paramilitaries.

[181][182] By 1992, the use of long-range weapons like mortars and heavy machine guns by the IRA had forced the British Army to build its checkpoints one to five miles from the border in order to avoid attacks launched from the Republic.

[188] On 1 January 1994, the IRA planted eleven incendiary devices in shops and other premises in the Greater Belfast area in a "firebomb blitz" that caused millions of pounds worth of damage.

The process, which was widely known of in nationalist communities, worked on a sliding scale of severity – in the case of a petty thief a warning to stop may initially be issued, escalating to a physical attack known as a "punishment beating" usually with baseball bats or similar tools.

A judgement as severe as death was frequently made public in the form of a communique released to the media but in some cases, for reasons of political expediency, the Provisional IRA did not announce responsibility.

[citation needed] This style of summary justice, often meted out based on evidence of dubious quality, by untrained investigators and self-appointed judges frequently led to what the Provisional IRA has acknowledged as horrific mistakes.

In 1992, The Provisional IRA attacked and eliminated the Irish People's Liberation Organisation (IPLO), which was widely perceived as being involved in drug dealing and other criminality in West Belfast.

[215] Thomas Murphy, a prominent Provisional IRA leader from South Armagh, has been the subject of repeated rumours of organised crime including diesel smuggling and tax evasion.

In 2006 both Irish and British security forces mounted a major joint raid on his farm, and in December 2015 he was arrested and put on trial in Dublin's Special Criminal Court charged with tax evasion.