In Lonely Are the Brave, my novel due out in April, a war hero warmly recalls parading through Brussels in December 1918 to celebrate the city's liberation from four years of German occupation.
Belgians had a soft spot for Americans too. The Commission for Relief in Belgium, which fed the country throughout the war, placed American delegates in major towns and cities, mostly collegians on leave of absence.
CRB delegates were essentially glorified accountants who pored over cargo manifests and inventory sheets while having to fight their way through red tape and withstand hazing by German soldiers convinced they were spies. Berlin tolerated the CRB as a means to keep Belgium placid and for public-relations value. But in Belgium, that tolerance wore thin.
The CRB never violated its neutrality pledge, but that didn't matter. CRB vehicles drew cheers from Belgians, which annoyed the occupiers, as did the Americans' casual confidence. As one delegate wrote, "The German stalks about Belgium as if he owned the country and the American as if he did not care who owned it."
I can just see those twenty-somethings excited by the power to act for a humanitarian project the like of which history had never seen—and bearing witness to a military occupation the outside world knew only by rumor.
As far as I know, the CRB story has never been told in fiction—I'm working on that now—but I've also got a book coming out in a couple months. It'll be a while!