Waking up to find your doctoral thesis being discussed on the Today programme is an odd experience. Having five years of research misrepresented in the global media is a bemusing and unpleasant one.

I have never accused Ian McEwan of plagiarising Lucilla Andrews; he acknowledges her at the end of Atonement, which is a patchwork of many factual sources and fictional models. Historical fiction relies on such sources. Atonement is built on dozens of them; Briony’s prose style, for example, moves through different phases and influences – the novel is written in Briony’s voice, appropriating the voices of her favourite authors. This tells us something about Briony’s personality. Robbie’s retreat through France is built on McEwan’s father’s own experiences, and details taken from histories of the Dunkirk campaign and diaries and letters now in the Imperial War Museum.

My doctorate looked at how a number of writers, born after the First and Second World Wars, go back to the historical record to create new fictional versions of those wars. I analysed the way that we use the past in fiction, particularly in relation to events outside our own memories. What can fiction do with history that history can’t?

The fact that the use of direct quotation from one text in the other has caused surprise raises, for me, the more interesting question of how we conceive of the use of history in fiction; how different authors use sources, and what kind of recreations of the past fiction can offer.

No-one reading Atonement and No Time For Romance together could fail to see the links – McEwan parachutes his luckless protagonist into Lucilla Andrew’s ward; she meets many of the same patients, has the same duties and often feels the same about them as Andrews does. But if McEwan is to create a historically accurate version of St Thomas’ Hospital in June 1940, should he not be praised, rather than criticised, for inserting poor Briony into the historical record? In my doctorate, I discussed how Pat Barker recreated Craiglockhart (the hospital Sassoon and Owen met in) with scrupulous care in Regeneration, and then added a fictional character, to explore the aspects of the situation which interested her. Similarly, Adam Thorpe’s novel 1921 uses factual and fictional source material not only to recreate the post-war era, but to reanimate the cultural issues and voices of the time – his novel speaks out of the period, as he put it, in the voices of the period, D. H. Lawrence’s prose style mediating T.S. Eliot and David Jones’s ideas.

McEwan’s critics seem less concerned with plagiarism than with a possible lack of courtesy towards Lucilla Andrews, who was unaware of her role in the genesis of Atonement. This has been picked up because McEwan is such a well-known and well respected author. But in actual fact, the issue isn’t about him personally, it’s about how novelists, particularly historical novelists, use primary material. Does a novelist who builds their narrative around historical facts need to acknowledge their sources? Would that depend on how much they had used, and how much it had been rewritten, transformed – given the "value-added" quality Thomas Keneally described?

What I find interesting is this question of what the right and proper way of using other people’s writing is. It is very difficult for anyone not to be influenced by vivid and well written words and not to replicate them, consciously or unconsciously. The novel is a hybrid form – based in reality, but making something new; this is particularly apparent in historical novels. Historical details, as McEwan has said, bring life and vigour to fiction. The imagination is crucial, but research brings truth. So what is the novelists’ responsibility to their sources? How can a contemporary novel speak to the past, or speak out of it, as Adam Thorpe puts it? Thorpe uses source material – details of the heatwave in 1921, and the cultural reaction to the First World War - as McEwan does, to take us back. "Come back", says Cecilia in Atonement. And fiction lets us. Natasha Alden recently completed her doctorate at St Hilda's College, Oxford. Her thesis on the uses of history in contemporary fiction was the first piece of analysis to bring the extent of the connections between Lucilla Andrews's work and Ian McEwan's novel Atonement to wider notice

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