From NetFlix:

Inspired by a true story, this heartwarming tale unfolds on Christmas Eve, 1914, in the midst of World War I. As the French, Scottish and German soldiers prepare to open their presents, a momentous event occurs that changes the destinies of four people: an Anglican priest, a French lieutenant, a world-class tenor and his soprano lover. Diane Kruger, Benno Furmann, Guillaume Canet, Gary Lewis, Dany Boon and Daniel Bruhl star.

I found another description:

In 1914, World War I, the bloodiest war ever at that time in human history, was well under way. However on Christmas Eve, numerous sections of the Western Front called an informal, and unauthorized, truce where the various front-line soldiers of the conflict peacefully met each other in No Man’s Land to share a precious pause in the carnage with a fleeting brotherhood. This film dramatizes one such section as the French, British and German sides partake in the unique event, even though they are aware that their superiors will not tolerate its occurrence

At first my reaction was, “This film is just too goody-goody”. But eventually the film got to me. It is a very musical film and features a folk-tune called “I’m Dreaming of Home” which is sung several times.

You will not regret seeing this film.