Tina Brown: And for her next trick...

In Evelyn Waugh's Scoop, a long-time favourite novel of the queen of New York's publishing and social scene, Tina Brown, the hero William Boot reaches the pinnacle of journalistic glory but prefers to slip quietly back to the country and write a nature column.

Brown, who grew up in Little Marlow, a picturesque village in rural Buckinghamshire, has long talked of the love that she and her husband, the former Sunday Times editor Sir Harold Evans, share for the British countryside. But don't expect them home soon.

Yesterday it emerged that Brown had finally clinched a deal to merge her groundbreaking news website The Daily Beast – named after the fictional newspaper in Scoop – with the world-famous but ailing magazine Newsweek. Brown will be editor-in-chief of the resultant Newsweek Daily Beast Company. For Brown, 56, the new role represents the latest challenge for an editor who has an unrivalled record in revitalising titles that have lost their lustre. Newsweek was sold by its former owner the Washington Post Co for the nominal fee of $1 in September.

Brown is the woman who transformed Tatler, brought Vanity Fair back from the dead and invigorated The New Yorker (although the changes she made to the august title were not to the taste of every traditionalist). Now she is hopeful of reviving Newsweek, partly with the digital energy of The Daily Beast – which was last year named by Newsweek's rival Time as one of the best five news and information sites in the world. Brown's two brands will form a "powerful dual platform", she says.

According to Stephen Glover, media commentator for this newspaper, she faces a difficult task. "She's a great believer in the web and it's slightly surprising to find her embracing a moribund part of the old media", Glover, a contemporary of Brown's at Oxford University, said. "You can see why that worked for her in the 1980s and 90s but Newsweek is going to need enormous transformation and investment."

One of the hallmarks of Brown's career has been her ability to find financial backing. She was only 25 when she became editor of Tatler and electrified the British media by spending the money of its wealthy new owner, the Australian Gary Bogard. She hired star photographers such as Norman Parkinson and David Bailey and assembled a roster of writers that included Nicholas Coleridge, Dennis Potter, Julian Barnes and Auberon Waugh, the first son of Evelyn.

She had interviewed "Bron" Waugh for Isis, the Oxford University magazine, and he had become a friend, helping her to get published by the New Statesman, where he was a columnist. At Oxford she was part of the literary set. Though she was intrigued by the Brideshead Revisited types that Evelyn Waugh had written about many years before, she never obviously aspired to join the titled classes, even if she has subsequently become Lady Evans.

Christina Hambley Brown was born into the affluent middle class, the daughter of self-made film producer George Hambley Brown who, when she was 11 years old, was filming Richard Attenborough and Jack Hawkins in Guns at Batasi, a melodrama set – just like Scoop – in a war-torn but unnamed East African state. Brown has previously delighted in describing her "subversive" childhood, during which she was expelled from three boarding schools for bad behaviour.

At the society magazine Tatler she pulled off the unlikely triumph of poking fun at the upper classes without driving them away and at the same time attracted new readers with cover stories on rising British stars. An early piece, called "Beasts of Belgravia", featured the titled ladies who wouldn't settle their bills at Harrods. Brown herself contributed irreverent pieces on stately home owners and satirical profiles of eligible bachelors under the pen name Rosie Boot, possibly named in honour of the Scoop hero.

One contemporary recalls the impact of Brown's editorship, crediting her with pioneering celebrity journalism. "What she spotted was this new thing called celebrity that none of us recognised at the time. She would put models and film stars on the cover. She had an instinct for what was going to work – almost like when Rupert Murdoch discovered that soap opera stories sold The Sun."

Having earlier had a relationship with Martin Amis, Brown began an affair with Evans, who divorced his wife in 1978 and remarried three years later.

Brown might now be Lady Evans but she has been a US citizen since 2005. The couple moved to New York in 1984 and Brown became editor of Vanity Fair, once again turning around a struggling media brand. This time her patron was the Condé Nast publisher Si Newhouse. As at Tatler, Brown assembled a formidable body of writing talent and photographers including Herb Ritts and Annie Leibovitz, who shot Brown's most talked about Vanity Fair cover, a 1991 shot of a pregnant and naked Demi Moore.

The following year, Brown became the first woman to edit The New Yorker. This time her stable included such illustrious writing names as David Remnick, Malcolm Gladwell and Simon Schama. But some veterans were outraged at what they perceived to be her disfigurement of an American institution, committing such sacrilege as hiring the magazine's first staff photographer, Richard Avedon. Some resigned, such as the late American novelist George Trow, who accused Brown of "kissing the ass of celebrity". In her response, Brown demonstrated her capacity for a withering put-down. "I am distraught at your defection but since you never actually write anything I should say I am notionally distraught."

She claims not to be surprised that she draws brickbats. "I'm an English person who has come to America and taken ... prime publishing jobs which Americans might feel should have gone to them. Of course there's a great deal of resentment," she told The Guardian in 1996. Even so, she built an unrivalled social set and the Evans's party guest lists came to define New York's elite.

When she departed The New Yorker in 1998, the magazine was still making massive losses. But Brown had found a new backer, the film mogul Harvey Weinstein. Together they created Talk, launching the magazine with Brown's most stellar party, to which Madonna, Robert De Niro and Demi Moore were taken by barge for an evening picnic at the foot of the Statue of Liberty by the light of thousands of Japanese lanterns. Part of Talk's strategy was to turn fine writing into movies. Simon Carr, The Independent's sketch writer, remembers pitching Brown an idea for a piece on fathers and children that had failed to arouse interest in Britain. "We met for breakfast and she said, 'That's brilliant, I want 10,000 words on that.' A contract came through for 10,000 words at $2 a word. She's quick, so acute." The article was the basis for the feature film The Boys Are Back in Town, based on Carr's memoir.

But Talk itself bombed, closing down in 2002. After producing a best-selling biography of Princess Diana, Brown went digital, founding with media magnate Barry Diller The Daily Beast in 2008. The site's best-known feature is the Cheat Sheet, a digest of what it considers to be the day's best reads.

The merger with Newsweek, which lost $30m last year, has raised the profile of both titles. But will it be easy for Brown to make the new business a success? "Up to a point, Lord Copper," as the original Daily Beast's foreign editor Mr Salter would tell the paper's owner, with calculated ambiguity.

A life in brief

Born: 21 November 1953, Maidenhead, Berkshire.

Family: Daughter of film producer George Hambley Brown and Iris Mary Kohr. Married to Harold Evans, formed editor of The Sunday Times; they have a grown-up son and daughter and live in New York

Education: BA in English literature, St Anne's College, Oxford.

Career: Freelanced for The Sunday Times, The Sunday Telegraph and Punch. Became editor of Tatler in 1979, and editor-in-chief of Vanity Fair in 1984. From 1992 to 1998 she was the editor of The New Yorker, moving on to create Talk magazine, which stopped publication in 2002. Wrote The Diana Chronicles, the biography of Princess Diana, in 2007. In 2008 she launched the Daily Beast, an online news magazine.

She says: "Nothing is better for a young journalist than to write about something that other people don't know about. If you can afford to send yourself to some foreign part, I think that's by far the best way to break in."

They say: "She is the best magazine editor alive. What more can I say?" Michael Kinsley, American writer