Every war is filled with myths, some big, some small. Growing up, BBC broadcaster Jeremy Paxman regularly heard of his "Uncle Charlie", his deeds and early death.

“The photograph was always on the wall,” Paxman remembers, sitting in an uncomfortable chair in a cordoned-off area at this week’s Conservative Party conference in Manchester.

“The family fable was that he had faked his age, joined up early, been killed on his 18th birthday, all that kind of stuff: the common first World War story, which turned out not to be true.”

Instead, his great-great uncle, Pte Charlie Dickson, was 24 when he joined the Royal Army Medical Corps, and just a year older when he died on the first day of the doomed Gallipoli landings.

Paxman's new book Great Britain's Great War seeks to examine the war through the eyes of those then living. The spur to do so came after the death of his mother, who, like others born in the years after 1918, had her perception of it guided by the belief that the soldiers were "lions led by donkeys".

However, Paxman argues, this was not the common perception at the time – not just in 1914, but even into the later years of the war, when the full horrors were known to many.

“She would have had her view very strongly coloured by the revision which begins in the late 1920s and goes through David Lloyd George’s memoirs,” he says.

The flowering of that perception of history is perhaps most prevalent in Oh, What A Lovely War, the 1969 musical directed by Richard Attenborough, which ruthlessly mocked the generals.

“My big beef is that we don’t realise that people saw the world very definitely in 1914. There had never been a war like this; they had been fed this view of Britain’s great imperial destiny.

“They knew nothing much about ‘abroad’. Most of them had never left their county, let alone their country. Those who read it through the prism of the 1960s do their history a disservice.

“We need to have in mind those who heard this call, rightly or wrongly. It is seen now through the prism of Sassoon and Brooke, Owen and so on [the war poets Sigfried, Rupert and Wilfred, respectively]. That isn’t how it was seen by most at the time.”

Generational shifts
History, he acknowledges, is understood anew by each succeeding generation, though Paxman disagrees fundamentally with the view that the war was a pointless sacrifice. "The suggestion that there was a callous indifference on the part of the generals is all very well, but to suggest that they consciously set out to have their own troops killed just doesn't make sense. It's nonsense."

Paxman argues that Britain’s decision to fight in the war was justified, since “stopping German domination of Europe was important”.

For many, the first World War is a forgotten past. “It is partly because the images are all black and white – it is one of the reasons why I insisted that the cover of the book was in colour. We tend to see things differently when we are used to high-resolution digital quality in colour. A hundred years is a very long time: four generations.”

But an understanding of it is necessary. “It is with us today because the changes that it wrought – their ideas about gender, their ideas about the role of the state, entitlements, the relationship between the citizen and the state – are still with us today. We don’t really question any of that.

“My personal view is that you cannot make sense of the present unless you understand the past and you cannot navigate the future without having a sense of where you have come from.”

Even the House of Commons vote in late August against military intervention in Syria requires a historical prism if it is to be properly understood, argues the Newsnight presenter.

“You can only make sense of that vote if you are aware of more recent history – everything since the end of the second World War. It has to be seen in the context of Suez. Yes, there was Blair and Iraq and the dodgy dossier, but that’s not all. If you don’t have that perspective, I don’t see how you can make sense of it all. Otherwise the actions seem like spasms, and they are not. We are all creatures of our past, whether we are aware of it or not.”

Over recent months, a debate has erupted in Britain over whether the war should be commemorated, or celebrated, along with differences over how Germany should be regarded. Musician Brian Eno and poet laureate Carol-Ann Duffy are among a group of people who are "very worried about it", he acknowledges, though "mainly because of Cameron's very clumsy use of words. They worry that it will be a celebration, but if it is done properly it won't be celebrated at all. We ought to recognise that something cataclysmic happened."

Facial reconstructions
Paxman recalls some of the unsung heroes he came across during his research, such as Harold Gillies, a "great man" who pioneered facial-reconstructive surgery. In all, 60,000 suffered head or eye injuries. "A man without an arm is a man without an arm. A man without a face is a man without an identity," he writes poignantly.

Some men, gruesomely deformed, screamed “kill me, kill me” as they lay in agony in their hospital beds, in wards that became known as “the chambers of horrors”.

By 1915, Gillies had persuaded the military authorities that action had to be taken. By the war’s end, a 1,000-bed hospital in Sidcup in Kent dealt exclusively with such cases.

“I didn’t know anything about that. I was really, really impressed. They were shocking stories. Some of the men never left the hospitals after the war. They got jobs as porters because it was the only place where people wouldn’t recoil in revulsion.

“Quite a lot of them got jobs as cinema projectionists. They come in before everybody else and leave after everybody else. And to think that that was the origins of the process which is now embarked on so lightly and so vainly by so many today.”

However, if his research has brought him closer to understanding his uncle Charlie’s motivations, it has not created a need in Paxman to see where he fell. His mother once went to the Helles Memorial to pick out his name from the 21,000 inscribed there, plucking “a few heads of lavender from a nearby bush”.

"I would say I'm very unlikely to do so. It doesn't impinge on my life in the way that it impinges on my mother's life, and I very much doubt if my children will go to pay their respects," he says.

Great Britain's Great War is published by Viking, £25