(The Movie "Joyeux Noel" is based on actual events, but is not historically accurate, it is FICTIONALIZED). https://en.wikipedia.org/wiki/Christm...

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, Scottish and German sides partake in the unique event, even though they are aware that their superiors will not tolerate its occurrence.

It is a fictionalized account of an actual event that took place in December 1914 when Wilhelm, German Crown Prince, sent the lead singer of the Berlin Imperial Opera company on a solo visit to the front line. Singing by the tenor, Walter Kirchhoff, to the 120th and 124th Württemberg regiments led French soldiers in their trenches to stand up and applaud.