Budget `97: Who is the man in the iron mask?

Dour child of the manse, Casanova, party in-fighter ... John Rentoul searches for the real Gordon Brown

He was born in Govan - the same Communist heartland of Glasgow's docks from which Tony Blair's father lifted himself - in 1951, the middle one of three sons of John Brown, a Church of Scotland minister.

That John Brown's body is still hale, in its eighties, and living in Aberdeenshire.

It helps build the Iron Chancellor image to be thought of as a dour presbyterian, and the phrase "son of the manse" has trailed him like a cloud of righteousness all his political life. But Gordon is not really a member of the New Labour, New Church sect, despite having joined the Christian Socialist Movement three years ago. Like most politicians, he stresses those bits of his background which help with today's message, whatever that may be. Last November it was to the CBI: "Business is in my blood." His mum brought him up short. When he said he understood all about stock depreciation and leveraged gearing because his mother had been a company director, she protested: "I don't know why Gordon is saying all this. I was only a director on paper. I would hardly have called myself a businesswoman."

Gordon went to school in Kirkcaldy, the other side of the Firth of Forth from Edinburgh. Possibly to maintain a hair-shirt image, he still supports Cowdenbeath, Scotland's fourth-worst football team. He took all his exams early, graduating from Edinburgh University aged 19 with a first in History. On the way he lost the sight in his left eye playing rugby, which emphasised his shyness and awkwardness - and made him more attractive to women. "He's got a glass eye because he was duelling with a scoundrel who insulted a lady," according to Julie Burchill. The first lady to get to him fitted the fairy-tale profile: she was a Romanian princess who dumped him after five years, complaining that it was all "politics, politics, politics".

Brown was elected to the Scottish Labour executive in 1977, and entered the maelstrom of the devolution battle. He led the campaign for a Yes vote, fought the hard-to-win Edinburgh South seat in 1979 and became chairman of the Scottish party. He had day jobs as a journalist and television reporter, but much of his energy was devoted to writing and editing political pamphlets and books, and to falling out with Robin Cook, already an MP and initially an ally, who responded pricklily to the driving ambition of his junior colleague.

He was elected to Parliament already burdened by great expectations. Whenever he was told he was headed for high office he would wince, and sink deeper into gloom. His worst moment came in 1988. When John Smith suffered his first heart attack, Brown stood in for him in the Commons; he roasted Nigel Lawson, at the height of his reputation as chancellor, and so Brown came top in the Shadow Cabinet election. "He's worried it's coming too early for him," said one of the growing band of Labour MP supporters. For 10 years he took the cautious, conventional route to the top. He turned down the first offer of a post as Scottish affairs spokesman and stuck resolutely to economic portfolios, being crowned with the shadow chancellorship five years ago. Learning from his brief experience as a journalist, he virtually invented the modern soundbite.

We knew his leadership aspirations were serious when he hired his own press secretary in 1993, the blunt and ferociously loyal Charlie Whelan. Whelan went to work immediately, and suddenly stories started to appear about Gordon's Girlfriends - a subject previously cloaked in a secrecy closer than any Budget purdah. A year later he took on the precocious Financial Times writer Ed Balls as his economics adviser. But the damage had already been done, with the party bruised by his no-taxing, no-spending line and journalists bored by his stilted sound-munches.

When, after endless tortured conversations with Blair in various "safe houses" all over the country, Brown finally pulled out of the leadership race to succeed John Smith, it was Peter Mandelson, his co-worker in the invention of modern political communications, who bore the full brunt of his intense frustration. Brown's capacity for feuding is one of the potential weaknesses of the Labour government. But he is not the humourless, grievance-nursing grouch he is sometimes made out to be. Privately, he is witty and charming. Even the most famous soundbite which bit him back, "post-neoclassical endogenous growth theory", only illustrates the danger of irony. After the impenetrable 91-word sentence from which the phrase comes, he paused and acknowledged ruefully to his audience that "endogenous growth theory is not the stuff of soundbites".

Whelan's energetic promotion of his boss is often misinterpreted by the Prime Minister's entourage - although Blair's own view is hard to fathom. A full-colour spread in the Mail on Sunday magazine two years ago was hardly helpful, portraying Blair as the dummy on ventriloquist Brown's knee, in the style of the Conservative election poster of Helmut Kohl. But Whelan's fingerprints were all over the article, which featured all five of Brown's known girlfriends, from Margarita (the Romanian princess) through Marion Caldwell (the lawyer) and Sheena MacDonald (the broadcaster) to Sarah Macaulay (current squeeze).