THE archive television footage from 1982 is familiar, at least to political anoraks. Gordon Wilson, the leader of the SNP at that time, orates sternly as a small group of delegates marches out of the conference hall in Ayr.
"I'm now convinced that the party will not recover its unity until all organised groups are banned," he storms. "Those of us who put Scotland and the party above narrow personal or political obsession cannot and will not tolerate behaviour which is divisive and harmful."
Kenny MacAskill's gait is at once recognisable, smartly dressed with a leather satchel tucked under his arm. In front of him is Stewart Stevenson, looking slightly sinister with his afro, beard, shades and black briefcase. Rob Gibson follows close behind, while Margaret and Winnie Ewing clap energetically on the conference platform, leading a partial standing ovation in the hall itself.
The "organised group" to which Wilson referred was the 79 Group, which had, for the previous three years, agitated for change within the SNP. Its aim was to create a Scottish Socialist republic but, after a traumatic political civil war, it was banned – or "proscribed" to use the parlance of the time – and within months, seven of its leading members were expelled, including Mr MacAskill and his close political associate, Alex Salmond.
Twenty-seven years later and not only is Mr Salmond leader of the SNP, but First Minister of a devolved Scotland. He puts his expulsion down to being a "brash young man".
Mr MacAskill, meanwhile, is Mr Salmond's justice secretary, Stewart Stevenson his transport minister and Roseanna Cunningham – the 79 Group's original secretary – his new minister for the environment.
It was Ms Cunningham, who in 1979 was the SNP's assistant research officer, together with her brother, Chris, who floated the idea for what became the 79 Group during that year's devolution referendum campaign.
On the Saturday following the referendum "defeat", Margo MacDonald, effectively the deputy leader, made an influential speech at a meeting of the party's national council. Her analysis was simple: while working-class Scots had voted "yes" in the referendum, Scotland's middle class had voted "no". The SNP, therefore, should look to the former to build support.
This meant, instead of maintaining its "all things to all men" approach, the party had to become more political, and therefore more left-wing.
Eight Nationalists sympathetic to this view met in Edinburgh on 10 March, 1979, and 30 to 35 people attended a second meeting at the Belford Hotel on 31 May. There, the "Interim Committee for Political Discussion" became the 79 Group. A decision was taken to print membership cards and elect officers, while three spokespeople were appointed, including Ms MacDonald and Mr Salmond. Although not the group's leader, the former Lothian councillor Stephen Maxwell became its intellectual force.
Within months, the 79 Group was producing campaign material – often of very high quality – and preparing to make its presence felt by fielding candidates for key positions on the SNP's National Executive Committee. Initially, this caused little concern among the "traditionalist" wing of the party, long-serving Nationalists such as Winnie Ewing and former leaders Arthur Donaldson and Robert McIntyre, who preferred ideology to be kept to a minimum.
Privately, and sometimes publicly, members of the 79 Group were scathing about the old guard. The "haphazard process" of elections for party office, Mr Salmond observed in a 1979 discussion paper, favoured "seniority and notoriety regardless of politics and, one suspects, merit".
But the 79 Group suffered internal divisions of its own. A major point of disagreement was republicanism. Pushed by Ms Cunningham and defence specialist Gavin Kennedy, other members, such as Mr Salmond did not consider it a priority. And when, for example, Ms Cunningham proposed opposition to a back-bench abortion bill at a 1980 meeting, the minutes record Mr Salmond querying the issue's political relevance to the 79 Group.
Ms Cunningham saw the group as transforming the SNP "from a motley collection of people" into a "truly political party which sees… the struggle for independence in a wider ideological framework".
This, she argued, required some ruthlessness, although she also identified ideological weaknesses in the group. "We claim to be decentralist socialists," she observed. "Let us start defining what we mean by this." Several events meant the 79 Group had limited scope for doing that. First was the controversial civil disobedience campaign under a "Scottish Resistance" umbrella.
The target was the economic consequences of Thatcherism, then seen as laying waste to Scotland's once-mighty manufacturing sector. Few in the SNP disagreed with the aim, but many were uncomfortable with the tactics, symbolised by the strategy's architect, Jim Sillars, breaking into Edinburgh's old Royal High School, the proposed site of the doomed Scottish Assembly.
Civil disobedience was at least, albeit briefly, SNP policy, but engagement with the Provisional Sinn Fein (PSF) was not. When the PSF wrote to the 79 Group suggesting a representative address its conference, Mr Salmond sensed trouble and moved to refuse the request. He won, but minutes of the meeting were leaked to the press and opponents of the 79 Group sensed an opportunity to move in for the kill.
The PSF affair coincided with the collapse of the civil disobedience campaign at the June 1982 SNP conference. Mr Salmond warned delegates the party would be adopting "a defeatist and cringing mentality" if it was dumped, but it was no use. When Winnie Ewing launched her own internal group, the Campaign for Nationalism in Scotland, at a noisy fringe meeting, the writing was on the wall for the 79 Group.
Later that month, Mr Salmond defended the group in a letter to The Scotsman. "Only a party willing to call for civil disobedience, primarily through organised labour, will be able to effectively back a democratic Scottish majority for a parliament," he argued
But when it emerged that the 79 Group's executive, which included Mr Salmond and Mr MacAskill, was planning to establish a Scottish Socialist Society outside the SNP, the party moved to expel them and five other members. Roseanna Cunningham avoided expulsion only by declaring she was not a member of the interim committee, while Margo MacDonald pre-empted it by resigning in protest. Ironically, Stewart Stevenson – who later admitted the group had "got too big for its boots" – served on the committee that considered, and narrowly rejected, Mr Salmond's appeal.
By expelling figures like Mr Salmond and Stephen Maxwell, wrote the historian Owen Dudley Edwards in The Scotsman, the SNP had "committed intellectual suicide". This, of course, was an overstatement, but while the 79 Group arguably did not quite succeed in recasting the SNP as a radical left-wing alternative to Labour, it did make the Nationalist movement more professional and moderately left-of-centre.
David Torrance is the author of The Contemporary SNP: From Protest to Government, published by Edinburgh University Press later this year.
THE 79 GROUP: WHERE ARE THEY NOW?
ALEX SALMOND: Elected as First Minister in 2007 elections.
KENNY MACASKILL: Appointed the Scottish Government's cabinet secretary for justice after 2007 elections.
STEWART STEVENSON: Became minister for transport infrastructure and climate change in 2007.
ROSEANNA CUNNINGHAM: Elected an MSP in 1999 and appointed environment minister in 2009.
MARGO MACDONALD – Elected as a list MSP for Lothian in 1999, since 2003 has been an independent nationalist MSP.
JIM SILLARS: The former SNP MP and deputy leader is now retired.
ROB GIBSON: Is now an SNP MSP for the Highlands and Islands.
STEPHEN MAXWELL: Now the associate director of the Scottish Council of Voluntary Organisations.
ROBERT CRAWFORD, CBE: A former chief executive of Scottish Enterprise, he is now chief operating officer of the South East England Development Agency.