The most important revelation about Alistair Darling is that a man whose favourite music is Pink Floyd and Leonard Cohen has been listening, over the past year, to Coldplay. As any fan will know, Coldplay’s most celebrated release was entitled ARush of Blood to the Head. As anyone who knows Mr Darling will tell you, the last thing he is likely to experience is a rush of blood to the head.

As a lawyer, politician and long-serving minister, he has risen smoothly to the top without putting a foot wrong.

Calm, self-possessed, unruffled by crisis, gaffe-free and hugely competent, he has served continuously in the Cabinet since 1997, moving through most of the great offices, from Chief Secretary to the Treasury, Secretary of State for Social Security, Work and Pensions, Transport, Scotland and finally Trade and Industry.

Now he stands on the verge of the biggest job of them all, Chancellor of the Exchequer, one for which he seems to have been earmarked for almost as long as his close friend Gordon Brown has yearned for the premiership.

Whether his new enthusiasm for rock’s most talismanic group is going to change the habits of a lifetime seems, on the face of it, unlikely. In some ways, that calm expression, the soothing tones, and the air of authority he imparts whenever crisis threatens, has been part of the Darling character for as long as anyone can remember.

At school and university in Scotland he is remembered as a well-behaved, hard-working pupil and student.

At Aberdeen University, where he read law, Professor Mike Meston, who taught him, recalls him as “a solid student, an excellent learner who thought for himself — level headed and remarkably normal.” That normality was to become critical during the most difficult periods of the Brown-Blair feud.

Although most people presume that Mr Darling was a Blairite — appointed and trusted by Mr Blair from the outset — he was also a friend of Mr Brown, and was able, at critical points, to step in and advise both sides to back off.

A former Cabinet colleague said yesterday: “He sets himself high standards, and expects others to do the same. He believes there are rules to be followed, and if they are not he will let you know.

“You only have to go into a restaurant where the service is not up to standard, and you soon find that out. Not that he will flounce out, but he will let you know that he is disappointed, which is far more effective.”

Although a quintessential Scot, soft-spoken, with an Edinburgh accent, Mr Darling was born in London, where his father, a civil engineer, was working. His mother came from the island of Lewis in the Hebrides. He therefore balances Gaelic romanticism and Edinburgh canniness.

Brought up on the move, wherever his father’s work took him, he was educated at Loretto, the highly respected Edinburgh public school, then went on to Aberdeen, where some of his West Highland cousins were students.

He trained as a solicitor, then switched to the Bar, where he “devilled” for Andrew Hardie, QC, later Scotland’s Lord-Advocate.

He also became a local councillor with Lothian Region at a time when Edinburgh politics was ferociously left-wing.

“Alistair was pretty left-wing himself in those days,” said a colleague, “but he always held himself in check, and simply got on with the business in hand. You could see he was ambitious, but he was never pushy, and never made enemies.”

His friendship with Mr Brown has been a critical factor in his rise — “you couldn’t slide a cigarette paper between them” said a friend —but despite their common background, they are very different in character.

While Mr Brown is a political animal to his fingertips, Mr Darling has always put his family first.

Married to Margaret Vaughan, a journalist, who was working on the now defunct Sunday Standard when they met in the 1980s, he regards Edinburgh, where they live, and Lewis, where they go as often as possible, as valued sanctuaries.

They have two children — Calum, 19, who is in his first year reading law at Aberdeen University, and Anna, 16, who is at high school in Edinburgh. Darling is close to them.

“Maggie is his rock,” said a friend, “and the most difficult part of his job is the need to take the early-morning plane back to London after every weekend.”

So demanding did the job come that he almost pulled out of politics altogether. “I’m not going to do this for the rest of my life,” he told friends. “I’ve got a young family, they deserve to see more of me.”

That was put on hold, however. But there is no doubt where his ultimate loyalties lie.

Ian Rankin, the author, and a close friend, says: “He is a charming, gentle soul, a more rounded human being than most politicians, and certainly not a bruiser.

“At home he can switch off politics, to become someone you can have a completely relaxed chat to. He talks a lot about books, and about music. The house always seems to be full of musical instruments.

“It is usually a bustling place, and there he is — the still, calm centre of it.”

It is a quality that he and his new boss will need to call on in full measure over the next hectic months of his political life.

Life and times

Place of birth: London, November 28, 1953

Education: Loretto school, Musselburgh and Aberdeen University

Previous Occupation: Barrister

Family: Married, 2 children

Constituency: Edinburgh South West since 2005, after his Edinburgh Central (1987-2005) seat was abolished

Current job: Trade and Industry Secretary

Previous government jobs: Transport Secretary (2002-06), Scotland Secretary (2003-06), Work and Pensions Secretary (2001-02), Social Security Secretary (1998-2001) and Chief Secretary to the Treasury (1997-08)

Opposition jobs: Spokesman on the Treasury (1992-07) and home affairs (1988-92)

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