Few living people, if indeed any, can claim to know the guilt and suffering of the First World War veterans as intimately as Crouch End oral historian Max Arthur.

Noted for his compilation of first-hand memories from the conflict, Forgotten Voices of the Great War – based around recordings of soldiers describing their experiences – Arthur also interviewed the final 21 British survivors for his tome, The Last Post.

Both books offer a reminder of the scale of human adversity during the war, which saw the first use of heavy artillery and took 37 million casualties, but the latter continues with an emotional insight into the consequences for those who outlasted it.

Transcribed from a handful of hour-long conversations with the veterans in 2004, Arthur captures the contrast between their relatively untroubled Victorian upbringings and huge hardships after the war.

He says: “I wanted to get a sense of perspective on their lives because war isn’t the only thing that happened to them, but it was the most traumatic thing. I never met a First World War soldier who wasn’t in some way traumatised by the events that he had witnessed.

“You didn’t notice the trauma just by meeting them, but they would talk about dark days after the war ended – and maybe a bit too much to drink.”

Unlike traditional historians, Arthur distances himself from any form of analysis to avoid diminishing the survivors’ dramatic personal accounts.

Instead, his skill lies in encouraging and consoling war veterans so that they are able to discuss their most suppressed feelings, occasionally for the first time.

When working on The Last Post exactly a decade ago, he discovered that the dwindling number of World War One soldiers – whose ages ranged from 104 to 111, including “the Last Fighting Tommy” Harry Patch and several quite reclusive characters – were stricken with the tragic guilt of survival.

Arthur compares this to the undue blame notoriously felt by survivors of a fatal car crash. This, coupled with a desire to ignore their past, made them difficult to interview.

“The veterans had an ability to cover everything up and get on with their lives,” he says. “They somehow got themselves together and never imposed what they saw or did on their families. They didn’t talk about their experiences because they wanted to put them away in a drawer and forget them.”

A former Royal Air Force member, Arthur has also turned interviews and archived tapes into publications about the Second World War. But he says that meeting the Great War soldiers was his pivotal period as a historian.

“They completely put life into perspective,” he says. “It was the seminal moment of my career to be able to interview these extraordinary men. They didn’t think that they were extraordinary, but they were.”

Arthur’s books emphasise the terror of conflict, together with the camaraderie that develops in defiance of its horrors, and are a case study in the humility of those who served in the trenches. “They were all unbelievably modest men. They had no thought of losing the war but also a great self-effacement.”

Rather than criticising modern leaders for not appearing to have learned the lessons of old-world diplomacy, the author believes that history is better suited to inspiring individuals in their everyday actions.

He advises people to try adopting a similar strength of character to heroes from the “war to end all wars” and suggests that striving to emulate the soldiers’ remarkable attitudes is an apt way of honouring their struggle.

“They teach us to just endure, no matter what comes your way,” he says. “People get upset when they are attacked or criticised, but the soldiers just learned to deal with massive onslaughts upon themselves – not only physically but mentally – and they had to wield a defence so that they didn’t fall to pieces.”

The brave veterans he came across have since died, along with all their counterparts from around the world.

But Arthur is certain that they would have wanted the centenary of the hostilities to comprise more than mourning.

“We must also celebrate the fact that the war was won despite the great cost,” he says. “The survivors always insisted that they wanted more joy in the world, so it would be nice if we could bring a bit of that into the commemorations.”