Amid all the books and films on the first World War, there was one story which has previously been untold: that of the boy soldiers. But now, using archive material and interviews with the ever-dwindling number of survivors, that is being put right. Nick Morrison reports.

PERCY Williams never forgot his first night under shellfire. He was in a dugout in the third line trenches when an officer came round to warn there was likely to be action that night.

"I was shaking and almost sick with fright," Percy recalled years later. "When the shelling started we were told to leave the dugout and we scrambled up into a trench that had been practically destroyed.

"Gas shells had been falling all night and saturated everything, covering our masks with a sulphur film. You couldn't see. I had stomach ache. I felt faint and sick and had to spew up, forcing me to take the gas mask off and vomit as best I could, trying not to breathe in.

"Between the din we could hear them shouting for stretcher bearers. I thought, 'Oh my God, I'm going to die, I'm going to die'. We did not know what was happening, not 50 yards either side of us."

Percy, a private in the Northumberland Fusiliers, was just 18 when he was sent to the front in March 1918. At the start of the war, the Government had resisted sending 18-year-olds to the front, but by 1918 the pressure of the German offensive proved too much for such sensibilities and the age limit was reduced.

But Percy, who was taken prisoner in the German spring offensive, was far from alone, and far from one of the youngest soldiers at the front.

Cecil Withers enlisted when he was just 17. A veteran of the Battle of Arras, he is now 106 and is one of a handful of soldiers who fought in the First World War who are still alive.

Then there was John Pouchot, 15 when he joined the Queen's Westminster Rifles in 1914. Before he was 16, he had won the regiment's first Distinguished Conduct Medal, and fought in the trenches until April 1915, when illness and exhaustion forced his evacuation from France. He later joined the RAF, was promoted to lieutenant, and was shot down and killed a month before the end of the war.

Other teenagers were also decorated. John Meikle enlisted at 16, won the Military Medal at 18 and a posthumous Victoria Cross a year later. George Peachment was 18 when he won the VC, going to the aid of his wounded captain in No Man's Land, an act of bravery which cost him his life.

Now the stories of these boy soldiers have been brought together for the first time. Combining interviews with surviving veterans and archive material, Richard van Emden has compiled a history of the underage soldiers of the First World War.

It was a project which began when he was a student at Newcastle University. While his fellow students were going to the pub, Richard would visit old people's homes to interview veterans of the Great War. And when he began to visit the battlefields in France the project began to take shape. "I was seeing the graves of so many 16-year-old boys, and it made me wonder how many of them are there," he says. "I started going through the Commonwealth War Graves Commission and found there were stacks and stacks, and it seemed to me that here was an amazing story that had never been written about before."

His research uncovered an incredible 250,000 underage soldiers in the British Army, although he believes this to be a conservative estimate, and the true figure could be as high as half a million. Many of those who lied about their age to enlist were never found out.

What may seem surprising to modern ears is how many teenage boys wanted to go to war, but this is understandable in the very different circumstances of 1914, although it had little to do with patriotic fervour, Richard suggests.

'The archetypal volunteer was a bored and frustrated teenager who could maybe have looked forward to working down the mines or in a steel foundry," he says. "They wanted to see a bit of action and be home by Christmas, and every girl loves a man in uniform. All these things played a part.

"King and country was important, but in essence it was that they could see nothing in their life, they wanted to do something different and the war was the most exciting thing that ever happened."

Almost as understandable, although perhaps less excusable, was the attitude of the recruiting sergeants. Although many children left school at 14 and by 16 would have two years' work behind them, leaving them looking older than their years, others were obviously still children, but were allowed to go to the front. The two shillings and sixpence they were paid for each recruit may also have played a part, although this later dropped to a shilling.

"To a certain degree I can forgive the recruiting sergeants, because there would have been boys who looked the part, but there were also those who were blatantly under age," says Richard.

Although there is no definitive answer to the question of who was the youngest soldier, the one with the strongest claim appears to be a Private S Lewis, who reputedly spent several weeks on the Somme and whose story appeared in the Daily Mail in 1916. He was 12 when he enlisted.

Some of the most incredible stories of these boy soldiers was of the teenage officers, who at 15 were leading companies of hardened veterans over the top.

One such was Philip Lister, who at 15 was commissioned into the 10th King's Own Yorkshire Light Infantry, and at 16 was an acting captain in the Battle of the Somme. Another was Reginald Battersby, a 15-year-old officer in the Manchester Regiment, who was shot in the arm and leg attacking a German machine gun post on the Somme. Had the gun not jammed he would have been killed.

"At the age of 15 or 16 they are looking after a company of 250 men. How many 15-year-olds could control 250 men for a month in a battlefield situation, many of these men being old enough to be their grandfathers?," Richard says.

Those who survived and came back from the war were irrevocably changed. Although this may have been true for all veterans, it was perhaps especially so for those who went to war as teenagers.

"They would have been mortified to have been left at home, but on reflection some of them said they wished they had never gone," Richard says. "They said it had ruined their life. But others said it made a man of them and changed their outlook on life. One of them said they came back saying nothing would ever stop them doing what they wanted to do again."

Some also felt an extra pressure to be successful in their lives after the war, as if only then could they justify their survival when so many of their comrades had died, and pay proper homage to the fallen.

Of the underage soldiers Richard identified, only 16 are still alive, and of those just five saw action in the trenches. But if his book owes a debt to those who provided him with their testimony, it is also a tribute to those who never came home.

And there is a consolation: two of the most visited war graves are of two of the youngest victims, John Condon, believed to be 14 when he was killed in May 1915, and Valentine Strudwick, who died at 15 in January 1916. Now their story is being told for the first time, perhaps visitors may pause at the graves of the other boy soldiers.

* Boy Soldiers of the Great War by Richard van Emden (Headline £20).