It was supported by many among the Irish-American community, as well the Palestine Liberation Organisation (PLO), which helped by sharing training techniques, weapons and funding.
However, it was in the 1980s that Libya's late leader, Muammar Gaddafi, supplied the IRA with its most devastating weaponry.
The Northern Ireland Affairs select committee has unveiled the highly politicised nature of the Westminster government's dealings with Libya and its role in one of the darkest episodes in contemporary British history.
Bankrolling the Republican movement
During the 1960s, the Provisional IRA was poorly armed, relying on aging Second World War weapons, many of which were depleted during the "Border Campaign" of 1956-1962.
When Gaddafi took power in Libya in 1969, he nationalised Libya's oil companies and used many of the funds to bankroll resistance movements, like the PLO and the Moro Islamic Liberation Front in the Philippines.
A large part of this was to buttress his image as heir apparent to the deceased Egyptian leader, Gamal Abdel Nasser, who was seen as the epitome of anti-imperialist struggle within certain threads of Arab nationalism.
For Gaddafi, the IRA was a comrade-in-arms, fighting British imperialism. With Operation Demetrius in 1971 - which saw the mass arrest and internment of IRA suspects without trial - Irish Republican discord with the British turned to support for the IRA.
Just a year after the Bloody Sunday massacre, in which 26 unarmed civilians were shot while demonstrating against internment, the Irish Navy boarded a ship off its coast containing five tonnes of weapons from Libya.
By 1981, "The Troubles" had threatened to wrestle Northern Ireland into the spiralling vortex of civil war, with IRA shootings and bombings commonplace, as well as brutalities committed by Ulster loyalist paramilitaries and British soldiers.
The tragic conclusion of the hunger strikes lead by Bobby Sands served to exacerbate the situation, but also brought new support from the IRA's prestigious benefactor. Gaddafi is said to have been impressed by the strikers' quest for political status, and promised fallout for Britain if it was not granted.
|For Gadaffi, the IRA was a comrade-in-arms, fighting British imperialism.|
However, it was not until 1986, when US bombing raids against Gadaffi launched from UK bases killed his adopted daughter, did the "Brotherly Leader" develop his support further.
A couple of months after the US air raid, cargo marked "property of the Libyan Army" was brought ashore the beach at Clogga Strand, County Wicklow, and shuttled north of the border.
The contents of these containers included 10 SAM missiles, and a tonne of Semtex-H plastic explosive. Manufactured in what was then communist Czechoslovakia, Semtex can produce a blast more powerful than a fertiliser-based explosive, and does not degrade.
For around 25 years, almost every bomb detonated by the IRA and other Republican splinter groups contained Semtex.
According to evidence given to MPs by Jason McCue, the legal representative of the victims of Gaddafi-linked IRA bombings, hundreds have died, and thousands injured due to Semtex bombings.
The 2003 invasion of Iraq by the US-led "Coalition of the willing" convinced Gaddafi to give up his WMD programme, and facilitate a compensation deal for the victims of the Lockerbie bombing.
According to an anonymous source speaking to Families Acting for Innocent Relatives, Gaddafi ordered companies named as BP and Shell to contribute no less than $2 billion to "the Lockerbie Fund".
In 2004, Tony Blair and Gaddafi were pictured in the Libyan leader's trademark tent, having just negotiated a BP deal. According to some reports, negotiations over the JERNAS missile system built by UK arms manufacturer MBDA, in a deal worth hundreds of millions of dollars, was also in the offing.
The renewed commercial relationship between the Libyan and UK governments was accompanied with a tuning down of criticism of the Libyans' sponsorship of terrorism.
When asked if he would lobby the UN in regards to Libya's IRA links in the same way he did with regards to the Lockerbie bombing, then Foreign Secretary Jack Straw gave an emphatic "no".
|Libya has answered questions about its involvement with the IRA to the satisfaction of the UK government
- Gordon Brown, UK prime minister
A year later, Blair's successor Gordon Brown stated that "Libya has answered questions about its involvement with the IRA to the satisfaction of the UK government".
'Tea and sympathy' unit
By 2009, Britain's Foreign Office had established the "Libyan Reconciliation Unit", tasked with dealing with the compensation claims levelled against the Libyan government.
This team was part of a broader programme of truth, justice and reconciliation for those victims and families of the troubles.
The head of the unit, Jonathan Dark, and FCO undersecretary Tobias Ellwood, were grilled by a cross-partisan board on Wednesday, asking why the $1 billion of Gadaffi regime assets frozen in the UK could not be tapped to compensate victims.
The meeting was heated, with Kate Hoey - a former Labour party minister who grew up in Northern Ireland - describing the Foreign Office team as "the tea and sympathy unit", due to its inability to make headway.
The DUP's Ian Paisley Jr said the unit was "a sop", and that the UK could circumvent international law to seize the funds.
Throughout the meeting, the domestic situation in Libya was cited as the core reason for the lack of progress, with the British government moving their diplomatic staff to Tunisia in light of the violence there.
Ellwood noted that within a matter of weeks, the FCO would know if they would have a Libyan government with whom they could conduct business with. Indeed the peace talks do seem to be at a decisive stage.
What will trump the FCO's concerns, commercial interests or truth and reconciliation, is yet to be seen. Meanwhile, with Belfast's Stormont government in a state of turmoil, and reports of Republican dissidents reorganising, the UK government will hope that most Semtex from those 1980s shipments have been tracked down and destroyed.
Nick Rodrigo is a freelance researcher working for the Afro-Middle East Centre based in Johannesburg. He holds an MA in the Theory and Practice of Human Rights from the University of Essex, and has previously worked with Iranian and Palestinian human rights organisations.
Opinions expressed in this article remain those of the author and do not necessarily represent those of al-Araby al-Jadeed, its editorial board or staff.