Literary London is in mourning for Pat Kavanagh, the glamorous doyenne of literary agents and wife of the novelist Julian Barnes, who died from a brain tumour yesterday. She was 68.

Margaret Drabble, one of Kavanagh’s stable of bestselling authors, said that she stood out not only for her beauty but also because she was unerringly discreet, genuine and frank in an industry rife with gossip and flattery.

Andrew Motion, the Poet Laureate, said that she was “immaculate in her looks, her manner and her attention to detail”.

Her formidable list of authors included Barnes, Joanna Trollope, Robert Harris, Sir John Mortimer, Ruth Rendell and the estates of Dirk Bogarde and Laurie Lee.

Away from the negotiating table, Kavanagh was known for the deep and lasting friendships that she cultivated with her authors, many of whom became regular visitors to the magnificent villa she shared with Barnes in North London. A fiercely private woman, Kavanagh nevertheless found herself thrust into the media spotlight on several occasions, most recently in September last year when she was one of the agents who defected en masse from PFD (formerly Peters, Fraser and Dunlop) to form United Agents.

Kavanagh was not the principal architect of the breakaway, which marked the culmination of years of tension between London’s oldest literary and talent agency and CSS Stellar, the US sports marketing company that bought the business in 2001.

Her decision to join the exodus, taking all her clients with her, was seen as a tipping point. In all more than 30 agents and 75 staff left PFD and set up a new venture together.

PFD and its withered client list was later sold at a knockdown price to a consortium headed by Andrew Neil, the former Editor of The Sunday Times. Kavanagh found the whole process very traumatic but said this year: “We’ve walked on coals and now we’re out the other side.”

Marriage to Barnes, the author of Flaubert's Parrot and A History of the World in 10½ Chapters, exposed her to unwelcome scrutiny. She had an affair with Jeanette Winterson, the author of Oranges Are Not the Only Fruit, but the marriage survived: so much so that when Barnes’s old friend Martin Amis left Kavanagh to sign with the rival literary agent Andrew “The Jackal” Wylie in 1995, Barnes cut all ties with him. Amis described the letter that he received from Barnes as containing “a well-known colloquialism. The words consist of seven letters. Three of them are Fs.”

Ion Trewin, the former editor-in-chief at Weidenfeld & Nicholson, knew Kavanagh well, from his professional dealings with her as a publisher, and as the father of Simon Trewin, the joint head of the books department at United Agents.

“She had exceptionally good taste at all levels of literature,” he said. “Most agents are known for one author or style of writing but she represented a phalanx of authors from Ruth Rendell and Joanna Trollope to Andrew Motion. As an editor if she came to you, you took her seriously immediately because she never wasted your time with rubbish.”

Kavanagh’s authors lined up to pay tribute. Robert Harris, who writes below, said that “there was a touch of Old Hollywood about her – she was very elegant and her age was a mystery but she combined that with being down to earth and would get involved in advising on what might be a good Christmas present for one’s wife”.

Drabble, whom Kavanagh represented for 40 years, said: “She was vitality itself and she knew everything about everybody but she was also famous for never gossiping about anything at all. I am completely devastated.”

Joanna Trollope would go clothes shopping with her. “My most beloved black jacket was because of Pat,” she said. “She phoned me and told me it had my name on it. She is going to leave such a gap. You believed her, trusted her judgment. Her praise was sparing but you treasured every nugget of it. She was a class act. A six-star class act.”

A statement from United Agents said: “Pat Kavanagh was an exceptional agent and great friend. We all owe her a tremendous amount; she was an extraordinary presence, who was much loved and will be greatly missed by her colleagues and clients. All our thoughts today are with Julian.”

Kavanagh’s brain tumour was detected just over five weeks ago. Barnes’s latest book, published in March, was a meditation on death, entitled Nothing to be Frightened of.

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