More than a century ago, some 140,000 farm laborers left their remote villages in China to work for Britain and France in World War One. Carrying out dirty and dangerous yet vital work in the trenches along the western front, their contributions to the Allies' war effort were significant, yet largely forgotten until the 21st century.

Today, the essential role these men played is finally starting to be recognized. So who exactly were the Chinese Labor Corps (CLC), and how did they change the course of one the world's deadliest conflicts?

For the centenary of Armistice Day - the date the guns fell silent on the Western Front in 1918 - descendants of the CLC and the British officers recounted their forefathers experiences for a documentary produced by the W J Hawkings Collection.

Why were Chinese farmers recruited for the European war effort? 

As casualties started to skyrocket in the thick of World War One, the Allies (France, Great Britain, Russia and Italy) were struggling to find the manpower for non-combatant roles. With most European laborers already fighting in the trenches, there was a need to bring in overseas workers to man Europe's docks and dig its trenches.

So in 1916, Britain and France started to look east for a force of manual laborers, giving birth to the Chinese Labor Corps (CLC).

Lured with the promise of European pay, the majority of those who signed up to the CLC came from remote farms in China's eastern Shandong province, then one of the country's poorest regions. It's thought that these workers were chosen because of their reputation for being particularly hard-working and physically well-built.

"My grand uncle was a burly chap, bigger than me, over 1.8 meters tall, like your typical Shandong hunk," says Wang Changjipe, a descendant of one of the CLC's ranks. "The reason why the British and the French recruited people from this region is because men from these parts are well known as fine male specimens," he adds.

Those who signed up left their farmhand roles in the Chinese countryside - many of them for the first time - first for training in the Shandong city of Weihai before heading to the port of Shanghai. From there, they were shipped across the Pacific to Canada to avoid lurking German warships, and in complete secrecy so as not to alert the enemy to the coming reinforcements.

Then there was a harrowing six-day crossing across the Canadian mainland in sealed trains, packed in and unable to leave the carts. From eastern Canada they once again boarded ships, only this time for Europe. Due to the appalling conditions during the long voyage, many would die even before landing on the continent.

What tasks did they have to perform?

Arriving in the French port of La Havre in 1917, the Chinese laborers were quickly put to work by the British and French in and around the war fields of continental Europe. Working at least 10-hour days, seven days a week with only three holidays a year, the men did a variety of operational tasks essential to the war effort: unloading guns at the docks, building roads, mending railway lines, and fixing tanks. 

One of the first jobs the Chinese men did was to dig trenches for the British army to retreat into, explains Ian Gibb, the grandson of an officer in Britain's 8th company of the CLC. But they brought their own particular work customs to the task.

While the British soldiers wanted to give the men a specific time to do the work, the CLC laborers wanted instead to be given a task. "They wanted to be told how many hundreds of yards of trench they should fortify," says Gibb. "And my grandfather said, much to the astonishment of the British officers, they'd done it by early afternoon and were back in their cabin drinking tea. And that's because my grandfather said they did everything quicker."

However, John de Lucy, the grandson of a British serviceman, explains that much of the work took a far more lethal turn as the war progressed. "Quite a lot of the photographs that grandpa took were of them pulling armaments apart. And where the armaments couldn't be disentangled, then they would take them out onto the beaches and blow them up," he says. "Some of the work was quite dangerous."

From dockers to sappers

Although the Chinese men had started off as laborers - promised before their departure that they would not be close to the front lines - by the end of the conflict, large numbers were called up to the front, doing highly dangerous work, such as searching for unexploded bombs.

"My own grandfather began as a chef working in the rear," says Cheng Lin, the granddaughter of Bi Quibe, another member of the CLC. "Then he went to the front to detect bombs and was eventually killed by one."

One descendant of a British servicemen who worked with the Chinese men recounts the strength that some of the men showed in the face of such adversity. 

"One of the Chinese laborers was very badly injured when they were doing their battlefield clearance because they exploded in his hand. He lost part of his hand and his stomach was ripped open," says Gibb. "The British officers never expected to see him again, but two months later he was back working, much to their astonishment, so that chimed in with an idea of how tough the laborers actually were."

Many others died in similar circumstances, while more lost their lives as German planes bombed the encampments of the Chinese men, who were not allowed to leave site except for work. For the laborers, it was their first time in an industrialized war, and their first experience of seeing the horrors of modern artillery and aerial bombardments. 

"Suddenly the workers were near this war but they were completely unable to move," says Mark O'Neill, Grandson of a British WWI Reverend. "They were in this enclosed space, this war was going on close to them, and how could they have any comprehension of this? So i think it was an extremely traumatic experience for them." 

And while the war ended in November 1918, that didn't mean such horrific experiences were over. In fact, the French forces demanded that after the fighting had stopped, the land be returned to the condition that it was before the war.

That meant clearing the contaminated land of exploded and unexploded shells, scrap metal, tanks, guns, and human bodies. With the French, British and Belgian veterans unwilling to carry out such tasks, the jobs fell to the Chinese and the other foreign workers to reconstruct Europe's killing fields.

Written out of history

Original estimates put the death toll of the CLC at around 2,000. However, the number of those working for the British Army alone is estimated by some sources to be closer 20,000. 

In France, Nolette Chinese Cemetery contains the graves of 841 Chinese men employed as a labor force by the British authorities during WWI. But despite Britain's 40,000 war memorials, it wasn't until recently that the Chinese men were honored with a monument of their own on British soil. Only a few graves can be found in the UK.

While France allowed thousands of the men to remain in Europe and form their own communities, today there are no descendants of the Chinese CLC in the UK because they were refused the right to settle after the war ended.

Such inequity also extended to the geopolitical level. Despite its vital role in the war, in 1919 China refused to sign the Treaty of Versailles after the Allies broke their promise that in return for their support, the Shandong peninsula under Japanese control, would be returned to China.

 "When the peace talks occurred in Versailles, China had a place at the table," says Gibb. "But the Allies paid no attention to China, did not give it anything of what it wanted, and in a political and diplomatic sense, the work and the sacrifice of the workers was for nothing."

On Remembrance Day in 2017, for the first time wreaths were laid at the Cenotaph in London to commemorate the Chinese laborers who came to support the Allies' effort in World War One. 

"In my opinion, they played a role in bringing an end to the war," says Zhang Jianguo, a former Director of the municipal archives in Weihai, a major seaport city in easternmost Shandong province. "If the Chinese laborers hadn't been involved, it's hard to say if the war would have been won or lost, or when it would have ended... We must not forget them."

Video editor: Tom Triebel