IT is tempting to think that until he was knighted in the New Year's Honours List, the current Chichele Professor of the History of War at Oxford University was plain old Hew Strachan.

I suppose you could argue the toss over the "old" bit – at 63, Sir Hew is fit-looking and, he says, still a decade away from retirement – but there was never anything plain about the emminent Scottish historian. Not when I first met him a decade ago and not now, in the noisy and bustling Edinburgh cafe he has travelled to from his family home, a farm near Biggar.

Leaving aside his teenage adventuring as a merchant seaman and on the Eurasian hippie trail, his time "bumming around" Sudan in a Bedford truck and his more recent trips to Afghanistan, Sir Hew is our foremost expert on the First World War, thanks to the first of his mooted three-volume history of the conflict. Published in 2001, it was the basis for a 2004 Channel 4 documentary series. Courtesy of his post at Oxford University, moreover, he has spent most of the decade since the invasion of Iraq enmeshed in what he coyly calls "Government and MoD-related stuff".

As well as the knighthood itself, proof of Sir Hew's standing in this last regard came last October when it was announced Prime Minister David Cameron was setting up a committee to oversee a £50m 2014 commemorative programme to mark 100 years since the Great War. Sir Hew will serve on its advisory board alongside Sir Jock Stirrup and Sir Richard Dannatt, former heads of the armed forces and the army respectively.

Other members include former defence secretaries Tom King and George Robertson and Birdsong author Sebastian Faulks. Sir Hew also sits on the Scottish national committee, set up last month. Talking about the commemorative project, Mr Cameron said the First World War was "fundamental to our national consciousness". Does Sir Hew agree?

"I think it shouldn't be and I'm always surprised how much it is," he tells me between mouthfuls of sandwich. "It's partly because it's taught – or over-taught perhaps – through the war poets, so people do have some notion of what it's about. And it's partly because we've continued to use the mechanism of remembrance that was derived from the First World War to apply to every war since. So all our war memorials, all our patterns of doing that are derived from the experience of that war."

In France and Belgium, where the war is viewed as one of liberation, plans are well under way for commemorative events. In that respect the UK has some catching up to do. But as well as organisational difficulties there are national sensitivities to take into consideration.

"There are countries that get their national identities turned into state identities," says Sir Hew, pointing to the example of the Turks who long ago re-packaged the First World War as the foundation of the modern Turkish state and who view Gallipoli as a great victory. "How are we going to cope with that at the same time as this notion that it should be about remembrance, commemoration and thinking about the dead?"

And, of course, there is Germany. "They're going to surprise themselves," Sir Hew says confidently. "Because this is a war that's easier to talk about than the Second World War, there's clearly a great deal of latent interest. At the last count there was something like 120 exhibitions and events planned."

That said, he adds, "it's still very difficult for the federal government. The Chancellor finds it very difficult to commemorate a war, full stop. It's the individual Lander (Germany's 16 federated states) that are doing it."

Although most closely connected with the universities of Oxford and Glasgow – he was Professor of Modern History at Gilmorehill between 1992 and 2000 – Sir Hew was born in Edinburgh and grew up in the New Town, not far from where we're sitting now. The family later moved to the grand residential area of Merchiston.

His father Michael Strachan had served in military intelligence during the Second World War – a comrade-in-arms was Enoch Powell, their friendship cemented on a 3000-mile truck journey from Cairo to Algiers following Rommel's defeat – and later became director of the Ben Line shipping company, then based in Leith.

Sir Hew was sent to prep school in Kent aged eight ("My aunt was married to the headmaster so I think my father got a reduction on fees," he laughs) and from there to Rugby School in Warwickshire followed by Cambridge University.

Or not quite. Using the fact he was being groomed for a career in the shipping industry, Sir Hew talked his way into the merchant navy for a round-the-world stint in 1968. "I served as a merchant seaman on a Ben Line ship," he explains. "I was allowed to do it on the basis that I would eventually come and join the company when I graduated – which is not what happened."

After graduating from Cambridge he made the first of his three visits to Afghanistan when he and some friends drove there via India and Iran. That was in 1971, "back when you could do those things". As tradition dictated, they went in a broken-down Volkswagen Kombi, though theirs had a GB sticker on the front instead of a CND emblem. "I think I know the inside of every car workshop between here and Calcutta".

His more recent visits have been far more serious affairs. In the spring of 2011 he was in Kabul and Kandahar and last summer, during what's known as "the fighting season", he visited Helmand.

"I think I felt pretty unfazed, actually," he says when I ask the war historian what the real thing feels like. "What made an enormous difference – and this is where I feel for soldiers – was that my wife was completely relaxed about my going and was jealous about me going. I then became aware that if my wife had been worried, the extra burden for me would have been greater."

The trip wasn't without incident, however: Sir Hew was in-country in April 2011 when rioting broke out around the United Nations Assistance Mission in Afghanistan (UNAMA) compound at Mazar-i-Sharif, which he was due to visit. Three staff members and four guards were killed in an attack on the base. Things were quieter for his return to the country in June last year. "There was the sense of an extraordinary increase in security," he says. "In 2012 we didn't have to go around with flak jackets and helmets on the whole time and have an escort. There were moments when we were travelling freely in Kabul, which simply wouldn't have happened in 2011". That said "there were one or two times when I thought 'Uh-oh, I might just have put myself in a slightly silly position'. But not too much".

Mind you, Afghanistan and the army are something of a family affair for Sir Hew. One of his two daughters served in Iraq and a son-in-law has served three tours of Afghanistan with 2nd Battalion, The Rifles. And the place itself doesn't seem to have left Sir Hew either.

"I do feel now that if somebody offered me a job in Afghanistan for six months or something I would take it, if I would wangle it," he confides. "The intensity of what people are doing, their commitment to doing the job well, the challenge and the difficulty of it, all that appeals to me enormously. Compared to the way we package our lives here, there is nothing quite like it. Is that adventurous or just stupid?"

That's the kind of question that's best left hanging, though if I were his publisher I'd say the second. On that note, how are the second and third volumes of the First World War history coming along?

He chuckles heartily. "I've made almost no progress," is his cheerful response. "The move to Oxford from that point of view has been a complete disaster. Current conflict is where the effort's had to go. Roll on retirement because that's when I'll get it done."

When the present is so demanding of your attention, I suppose it's hard to give up time for the past.

sir hew strachan History professor