Pat Barker admits, with a rueful laugh: “I do sometimes groan when I hear the words ‘first world war’. In fact, I usually groan.” As she recognises, her acclaimed trilogy of novels about the Western Front – Regeneration (1991), The Eye in the Door (1993) and the Booker-winning The Ghost Road (1995) – has entrenched an image of her as a writer obsessed with that period. Over the past decade, she has tried to distance herself from it by producing fiction set in the present day. But with her new novel, Life Class, she returns to the era she “never intended to write about again”.

Why has she gone back? Because, she explains, she became fascinated by the group of talented young artists – Christopher Nevinson, Mark Gertler, Paul Nash, Dora Carrington – at the Slade just before the war. How characters such as these would react to “the enormous event that took over everybody’s individual lives” was a question that excited her. “I didn’t have a sense of déjà vu,” she remarks, “because the people involved are all very different from those in the Regeneration trilogy. They’re much younger and much more naïve. They’re undamaged and unformed. They don’t bring anything to it really, except the capacity for being shocked.”

What will shock and change them – and their art – is the calamitous occurrence that she seems overpoweringly impelled to write about: not the first world war particularly, she stresses, but war itself. Her intense interest in “this tremendously important event that is almost uniquely capable of revealing what human beings are capable of when put under supreme pressure” is apparent everywhere in her fiction. If imaginations had colours, you can’t help feeling, Barker’s would be khaki. Besides her first world war trilogy, she has made fictional sorties into numerous other combat zones. Her previous book, Double Vision (2003), focused on war photography and a reporter burnt out by experiences in Sarajevo and Afghanistan. A recent short story, Subsidence, traced aftershocks of the war in Iraq. Warfare on a more local scale engages her, too. Gender antagonisms crackled through her first book, Union Street (1982). Prostitutes under attack by a serial killer were the subject of a novel galvanised by the Yorkshire Ripper murders, Blow Your House Down (1984). Class hostilities – and conflicts caused by psychotic criminality – receive alert attention as well.

Talking about her work in her bookcase-crammed home in a leafy Durham street, she seems at a civilised remove from the trauma and turbulence of so much of her fiction. Just perceptibly burred with a tinge of the northeast, her speech is precise and measured. A good-humoured readiness to explain, a relish for analysis and a concern with clarity and accuracy indicate what an excellent teacher she must have been when she worked in further education – a job she loved – in the 1960s.

From her early years, war impinged on her consciousness.

As she is “very much aware”, she owes her existence to a wartime fling when her mother, Moyra, became pregnant after a drunken night out while in the Wrens. Who the father was, Moyra never knew. Differing versions (“There was a very great storytelling gene in my mother”) inventively featured a rapist, a heartbreaking marine and a high-ranking RAF officer. Pat, who grew up believing that her father had been killed in the war, was passed off by her mother – whom she always called by her first name – as a younger sister. There were, she grins, “a hell of a lot of ‘sisters’” after the war, “girls with children 18 years younger than they were, who were their ‘sisters’.”

The first world war seemed close to home, too. After her mother married and started another family, she was brought up by her grandmother and step-grandfather – who had received a bayonet wound on the western front. “The bayonet was stuck in, but it wasn’t twisted, because his officer shot the man who was about to twist it. If you twist and withdraw, it’s a difficult wound to survive. When I was a girl, I tended to take the bayonet wound for granted – that was what happened to you if you were in the first world war. But, of course, it was actually a very rare wound,” she goes on, with a typical concern for factual accuracy. “Only 3% of total wounds were bayonet wounds, because close combat of that kind was comparatively rare.”

Not that her grandfather’s wound is a mere statistic in her memory. Her recollections of it are vivid and palpable. “I used to stick my finger into my grandfather’s side. He used to get washed when he was going out to the British Legion in the evening, get washed at the kitchen sink, which made the wound obvious. It was quite a dramatic wound – as they were, of course, because it isn’t like a surgical wound. It’s very messy.”

What impressed her most was that her grandfather “never talked about it at all”. It was silence, she says, that first whetted her curiosity about war. “All my interest in war comes from what is not said – what was not said about my father, what my grandfather didn’t say about his experience.” True to this, she observes: “There are lots of speech impediments in my work, of one kind or another.” It’s no accident, you realise, that some of Regeneration’s most riveting scenes involve a man stunned into dumbness by unspeakable horrors witnessed on the Somme, and a doctor brutally eager to jolt war-trauma victims out of mutism by severe electric shocks to the throat.

Barker’s novels noticeably excel at dialogue. She is expert at conveying a keen sense of intellectual exchange, of people who not only talk, but listen carefully to each other. In Regeneration, therapy sessions at Craiglockhart hospital quiver with suspense, as Rivers, the army psychologist treating patients pathologically desperate to suppress and repress, watches for “the moment when the gesture subverts what’s being said, rather than reinforcing it”. Dialogue, Barker declares, is “absolutely essential” to her as a novelist: “If the dialogue isn’t working, the characters are not working either.” One peculiarity, she says, is that: “All my internal speech is always northern working-class, no matter who the character.” When reading starchy upper-class enunciations in Life Class (“As for inviting two young men for the weekend... You know, you can only flout convention so far before you start to get a reputation”), it’s interesting to reflect that they first made themselves heard in a Tynesideaccent.

In her early years, she remembers, “we were poor as church mice; we were living on National Assistance – ‘on the pancrack’, as my grandmother called it”. Even in these circumstances, thanks to her grandmother – who steered her through grammar school and doughtily tried to keep pace with her, learning French and reading Shakespeare – there was “never the slightest feeling that you were only a girl, ‘You won’t go to university, you’ll only get married’”. University was the LSE, where Barker read international history, with an emphasis on diplomatic history. This wasn’t, she smiles, entirely to her taste, because “the thing about diplomatic history, of course, is that you do tend to leave out the wars”. The first world war, she jokes, would feature as “Failures in Communication between 1914 and 1919”.

After going back to the northeast, she met and married David Barker, an academic zoologist and neurologist – now a professor emeritus at Durham University – who encouraged her to concentrate on her writing, and with whom she has two children. (Anna Ralph, her daughter, has just published a strong debut novel.) Her fictional breakthrough came when Angela Carter, her tutor on a writing course, showed Union Street to Virago. It published this and several subsequent works, including a novel about a working-class woman, Liza’s England (which it insisted on renaming The Century’s Daughter after its Scottish rep said the original title would deter buyers north of the border).

Winning the Booker for The Ghost Road in 1995 made “a gigantic difference”, greatly boosting Barker’s sales and reputation. Though after it, she remarks, you are “writing in the shadow of your own success”. Set in contemporary Newcastle, Another World (1998) was a novel she found “very difficult to write”. Symptomatically, it came most alive when she introduced the character of Geordie, a centenarian war veteran who dominates and energises the book.

Her next two novels, Border Crossing (2001) and Double Vision (2003), cured her of wanting to pursue what she calls “a certain kind of contemporary relevance”. “In many respects,” she feels, “it’s easier to write innovative and original and startling things about the past. And it’s not just a matter of the writer being more capable of doing it. It’s that people are more capable of receiving it. If you are writing about the contemporary scene, at some level, people know what they think about it. They know what they think about the war in Iraq, they know what they think about whether we should have got involved in Kosovo, and you get almost a knee-jerk reaction. Whereas they don’t know enough about the past to know what they think, and so you get a far more open mind.”

Written in accord with this belief, Life Class seems to have been struggling to emerge even as she worked on Double Vision, whose theme is “the extent to which atrocity can be shown”, and whose epigraph, from Goya’s Disasters of War, is: “One cannot look at this. I saw it. This is the truth.” While exploring present-day dilemmas about the ethics and aesthetics of portraying war damage, she was “all

While it would, she says, “be leading people the wrong way to look for actual historical equivalents”, characters in the foreground of Life Class share unmistakeable traits with Nash, Carrington and their circle. In particular, a progressive painter, Kit Neville, is reminiscent of Nevinson, an artist Barker finds intriguing. “He was doing these machine-led paintings from about 1910 onward, and he got his vision of the first world war faster than anyone else, because he was already painting people dominated by machines and industrial landscapes. He was preadapted.”

One real-life figure in the book is Henry Tonks, the professor at the Slade whom Barker admires, not just for his inspirational teaching, but because of his contributions to wartime plastic surgery. A surgeon before he became an artist, Tonks recorded the differing stages of pioneering reconstructive facial surgery in a remarkable series of drawings and pastels that he felt could never be publicly displayed because they were too horrific, and would violate the privacy of the mutilated soldiers who were their subjects. “That interests me,” Barker says, “because it asks fundamental questions. It’s that fundamental thing about art – that it’s about getting the truth for yourself, rather than thinking about any even possible audience.”

She has already completed several chapters of a successor to Life Class, in which its characters will be confronted with war’s personal and artistic challenges. And there’s no doubt she will continue. “I enjoy doing it. I enjoy creating other people. I enjoy asking myself questions about the world and answering them in this particular form.” The bugle won’t be sounding just yet on her distinguished literary engagement with war.

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