I reread Birdsong before interviewing author Sebastian Faulks, awed anew by his epic depiction of the First World War’s ever active battlefields.

Adapted first by the BBC for TV, and then as a stage show now on its fourth tour, the play is finally being put to bed, Oxford its final destination.

Which means that Faulks is in a reflective mood when we speak, determined to see his most famous work off with a bang, and volunteering himself for a turn on stage during the run at the Playhouse.

“Let’s not exaggerate the importance of my part,” he chuckles. “I’m a soldier in a group with about four lines and then I’m a policeman. So if I do mess up I’m sure the others will gloss over it.

“And as it’s also the centenary of The Armistice, it seems a fitting time to bring everything to an end. It’s had a great run, played to some really amazing audiences and been a great success, so I’m happy. It’s great fun and I do enjoy it.

“I love the theatre though. I was brought up near Newbury and visited Oxford often with my mother, an avid theatre-goer. We would go to the Playhouse and New Theatre and I remember seeing a pop group called The Springfields with this great girl singer [Dusty] – you knew she was going to be something even then."

So was it hard to hand over his best known works? “If I had my time again there are so many things I would do differently but Eddie Redmayne and Clémence Poésy were good, that’s all I will say.

Does he feel pigeon-holed by Birdsong then? “No because I’ve written 12 to 13 books since, which have sold well and been well received. To have a book as a locomotive pulling the other carriages along has been really good for me.”

Considering these include Charlotte Grey, made into a Hollywood movie starring Cate Blanchett, and Devil May Care, a post-Fleming James Bond novel and Penguin’s fastest selling hardback fiction title ever, that’s saying something.

And yet Birdsong not only resonated with a new generation but also educated them. Was that the point? “In the 1960s the first and second world wars were well memorialised by The War Graves Commission and the British Legion but people wanted to move on.

“And then Vietnam came along and people became much more pacifistic. It was just the atmosphere of the time, so when I began thinking of writing a book, it seemed a good era to concentrate on.”

So where did he start? “You react to a hunch. You know what you want to write about, but need specific research to enable you to do so. So I spoke to a group of men who fought on the Western Front, and visited with an group of veterans, which gave me a real sense of connection with the time and place, as well as having their blessing to tell this story.”

Did he feel a great sense of responsibility as a result? “No, because the experience of these men wasn’t properly understood or valued by our society. You just need to spend a lot of time thinking about the book you are about to write, researching it and reading about the characters.

And yet his characters are so solitary. Is that drawn from his own experiences as a writer? “It’s more interesting to put people in different situations and see how they respond,” he says.

Faulks’ former job as the first literary editor of The Independent and deputy editor of the Independent on Sunday must have helped? “I had 15 very sociable years working as a journalist on a newspaper. Subsequently 25 years later sometimes I wish for a bit more company, because it is solitary so you have to be careful, because it only takes a few long lunches....although when I’m in the throes of writing it’s a full on 8-10 hour day.”

He doesn’t get lonely then? “No. I have a very busy family life; a wife and three children. I miss my colleagues and friends in journalism, but journalism is a very different business these days due to a lack of resources. so it’s no longer a journalism I’m interested in. I was just fortunate to catch the end of Fleet Street when newspapers had the money and time to commit properly.

So will he stay in London ? “I am intending to unless something catastrophic happens like Boris Johnson becoming Prime Minster, in which case I’ll move abroad.

As for Paris Echo, it’s out in September by which time Faulks might have also finished the play he’s working on. “I’ve never written a play before. It’s about the madness of love so I have no idea if it will be any good. I’m aiming for 90 minutes without an interval, but I’ve only done 20 pages so we will see.”

“Paris Echo on the other hand is about how much culture and history we need to know to live a worthwhile life, and if you know a lot does it make your life more valuable? It’s not a reaction to anything, just a question set in the present day.”

Birdsong, Oxford Playhouse, Monday-Saturday. 01865 305305 or oxfordplayhouse.com