France has paid tribute to an often forgotten corps of 140,000 Chinese labourers who dug trenches, worked in weapons factories and, for many, lost their lives helping France's effort in the first world war. Defence Minister Jean-Yves Le Drian laid a wreath in front of a commemorative stele in a park in Paris' Chinese district to honour the little-known contribution of these labourers, before a military band played Le Marseillaise . "Their presence at the side of the French ... on the frontline of the war... remains one of the forgotten stories of the great war," said Le Drian. "France does not forget those who came to our aid... at the rear or at the front, in factories or in the trenches, the help of these Chinese workers was decisive at a terrible time in our history." As war raged in 1916, France and Britain were finding it hard enough to drum up fighting men, let alone labourers to dig trenches, work in factories, collect dead bodies or perform any number of manual tasks. Both countries signed a deal with China to send workers to help the Allied war effort. Many were peasants lured by the prospect of a better life. Le Drian said the majority of these workers came from northern China. "They left their villages, their families ... crossing the ocean for a war which they did not yet know, but which would become theirs." He said the months-long voyage in itself left some dead, and the fate of those who made it to France was often dire. They lived in dilapidated buildings, separate from other workers, and earned "a miserable wage", the defence minister said. "In their own way they were, on the economic front, soldiers for France as it was engaged in all-out war." Some 20,000 Chinese lost their lives for France. After the war, 3,000 remained, forming the country's first Chinese community. One hundred years after the start of the war, the largely forgotten contribution of the Chinese has come under the spotlight and a photo exhibition is also being staged in Paris.