by Xinhua writer Jianmei Xu

WASHINGTON, May 24 (Xinhua) -- The year 2018 marks the 100th anniversary of the end of the First World War and a big question is lingering -- how could we mourn all of those who lost their lives?

More than 16 million people were killed in the first deadliest global war in human history and most of them died so young, nameless and miserable on foreign soil.

To see a world in a grain of sand, and to tell a young U.S. soldier's "sad but poignant tale" that may map the tragedy of millions of lives during WWI, three 84-year-old American men made a documentary movie "WWI: An American Martyr."

On Wednesday evening, days before the annual U.S. Memorial Day on the last Monday of May, the Harvard Club of Washington, D.C. held a WWI Centennial commemorative event showing the 22-minute movie, co-directed by 1955 Harvard graduates Edward Nef and Douglas Hartley, with voice-over provided by William Flanders, a 1955 Yale graduate.

"It was an amazing opportunity to produce a film such as this, which helps to bring to the public's attention the enormous sacrifices made for a cause commemorated 100 years later." Nef said at the event.

The film narrates the life story of Charles Fletcher Hartley, Douglas' uncle whom he never met. Charles grew up in the United States and left with his family for England at age 16 in 1913, one year before WWI broke out. He graduated from Harrow School in 1916 and had been accepted by Cambridge University before joining the British Coldstream Guards, the Queen's own Infantry Regiment.

The United States declared war against the Axis Powers in April 1917 and Charles had been slated to help train U.S. army machine gunners before the massive U.S. troop movements into France. However, Charles followed his regiment to fight in Cambrai, France in November of that year and was shot in the head and killed there in the following month.

"Since my childhood, I've been hoping to find the monument to my uncle in a little town in France named Fontaine-Notre-Dame... My grandfather erected it after the War." said Douglas Hartley, a former U.S. Foreign Service officer.

"Making it (the movie) personal for one person, and then showing the story around that person, I think that is what really makes it touching," George Petasis, Chief Information Officer of Georgetown University Law School, told Xinhua at the event, adding the film helps the audience to get a real connection to the war 100 years ago.

To produce this documentary which took them 16 months, Nef and Hartley visited many battlegrounds and cemeteries in Belgium and France. They found the place where Charles was killed and the monument in a French farmer's field.

"This was awesome and so tragic, seeing so many countless tombstones, row upon row, often with no names, so many marks of sorrow left alongside the tombstones by grieving visitors," Nef and Hartley recalled, noting the sharp comparison with the pastoral landscape they saw around.

"The only thing which could destroy this idyllic scene was the intrusion of man-made instruments of war: tanks lumbering through the fields and woods; troops rushing headlong into huge fusillades, bombardments wreaking destruction, and what for?" they asked.

More than four million American families sent their kids to serve in uniform during WWI, among them 116,516 U.S. soldiers died from combat and diseases while another 200,000 were wounded, according to data from the U.S. WWI Centennial Commission website.

Those young people who died in WWI, a war that had changed the whole world but failed to become the war to end all wars, should never be forgotten, said the commission's Public Affairs Director Chris Isleib in his keynote speech at the event.