Obituary: Martin McGuinness, IRA fighter who became a linchpin of peace

Martin McGuinness, who has died from a rare heart condition at the age of 66, was with Gerry Adams the dominant figure in Irish Republicanism through four decades of armed struggle and subsequent political manoeuvrings.

He was in turn the Irish Republican Army's chief of staff, Sinn Fein's chief negotiator, minister of education in David Trimble's short-lived executive, and deputy first minister, initially to Sinn Fein's arch-enemy Ian Paisley. And on June 27 2012 he shook hands with Queen Elizabeth.

While Adams could portray himself as a politician, McGuinness had his finger on the pulse - and trigger - of terrorism. Yet Sinn Fein selected him, not Adams, as its senior ministerial nominee when the Good Friday Agreement was implemented. And Unionists found McGuinness less difficult to deal with than the prickly Adams, even finding him magnanimous.

James Martin Pacelli McGuinness was born in the Bogside on May 23 1950, the second son of Tom McGuinness, a foundryman, and his wife, Peggy. He left the Christian Brothers' technical school at 15, working in a butcher's shop after a garage rejected him because of his religion. He gave up butchery on August 8 1969, the day Catholics repelled the Royal Ulster Constabulary and B-Specials in the "Battle of the Bogside", which led to the British army being sent in.

He joined the IRA when the troops arrived and, in numerous gun battles, made his reputation as the hard man behind the barricades in the "no-go" areas of the Creggan and the Bogside.

McGuinness rose rapidly up the Republican hierarchy - switching from the Officials to the more active Provisionals - through his decisiveness and force of personality, and the internment of senior Republicans which gave the street fighters their chance.

By 1971 he was unchallenged commander of its Derry Brigade - admitting to the Bloody Sunday inquiry three decades later that he had been the Provisionals' No2 in Derry but strongly denying he had fired the first shot.

Bloody Sunday - the shooting of 13 unarmed civilians by British paratroops in January 1972 - left McGuinness feeling that he had let his people down by not going on the offensive. A wave of cold-blooded killings of soldiers and Royal Ulster Constabulary men followed.

Joining the IRA in Bogside at the start of the Troubles, the 1.8m teetotal McGuinness became its most powerful figure in Derry, and foil to the Belfast-born Adams. From 1997 until 2013 he was Sinn Fein MP for Mid-Ulster, like Adams refusing to take the oath or his seat.

With impeccable credentials as a man of violence, he was trusted by IRA hardliners. So Adams preferred him to head Sinn Fein's negotiators for the ceasefires of the 1990s when the movement claimed to have forsaken the Armalite for the ballot box. (When McGuinness heard the phrase, he asked: "What the f***'s going on?")

Like Adams, McGuinness was unsullied by the 1975 ceasefire which the Provisionals came to regard as a sellout - he was in jail in the Republic of Ireland - and the two devised the cellular structure under which the IRA regrouped when repulsed by Northern Ireland secretary Roy Mason's security drive in the late '70s.

McGuinness was never convicted of a terrorist act. He was twice imprisoned in the republic for IRA membership; in Northern Ireland, where he was held on similar charges in 1976, he otherwise faced only public order charges.

The ultimately successful negotiations with John Major and Tony Blair's governments and the Northern Ireland parties brought his life full circle. In 1972, aged 22, he was one of the IRA leaders flown to London for a secret meeting with Northern Ireland secretary Willie Whitelaw; he berated Whitelaw for claiming British troops would never fire on unarmed civilians, bitterly denouncing Bloody Sunday.

While Adams could turn on the charm, McGuinness presented during the Troubles an aspect of unremitting menace, blaming the British government for each Republican murder. He never condemned such atrocities, but did once warn the IRA not to be "the initiators of further injustices".

A devout Catholic, he maintained that "God will understand the pressures we are under". His commitment to the armed struggle was fundamental. In 1984 he told a Republican funeral: "We recognise the value and the limitations of electoral success. We recognise that only disciplined, revolutionary armed struggle by the IRA will ever end British rule."

A decade later he joined Adams in winning over the IRA's army council to temporary support for the peace process, arguing that there was "nowhere to go but the negotiating table". And having seized the "historic opportunity" for talks, his message in those talks was uncompromising.

His involvement in electoral politics stemmed from the 1981 hunger strike which created martyrs in Bobby Sands and the other prisoners who died and, through the by-election successes of first Sands and then Owen Carron, created an electoral base Sinn Fein could not disavow. He gained value as a public figure, and to reduce the risk of rearrest gave up being chief of staff for a nominally political role.

He leaves a widow, Bernadette, three sons and a daughter.

1950-2017