Speaking about a documented event, I just finished reading an old book I came across titled "The Great War as I Saw It, by Canon Frederick George Scott, C.M.G., D.S.O." Late Senior Chaplain , First Canadian Division, C.E.F." Copyright, Canada, 1922.

Here are a few excerpt from Chapter 9 titled "Our First Christmas in France".

Taking my bag with communion vessels and as many hymn books as I could carry , I was motored over on Christmas Eve to the 3rd Brigade headquarters at Petit Moncque Farm. Further up the line there was a barn known as St. Quentin's Farm, which for some reason or other, although it was in sight of the enemy, had not been demolished. I was determined therefore to have a service of Holy Communion at midnight (this they did and sang Christmas songs as well.).
The next morning (being Christmas) the rains had let up and it was a beautiful sunny day. The men were in high spirits and shaking hands with the words "Merry Christmas".

The Colonel had given the orders to the men not to fire on the enemy that day unless they fired on us. The Germans had evidently come to the same resolution. Early in the morning some of them had come over to our wire and left two bottles of beer behind as a peace offering. I actually got out into "No Mans land" and wandered down it. Many Christmas parcels had arrived and the men were making merry with their friends ( and so on.).
Not long after midnight , once again the pounding of the old war was resumed, and as I went to bed in the dugout that night, I felt from what a sublime height the world had dropped. We had two more war Christmases in France, but I always look back upon that first one as something unique in its beauty and simplicity.

When I stood on the Parapet that day looking at the Germans in their trenches, and thought how two great nations were held back for a time in their fierce struggle for supremacy, by their devotion to a little Child born in a stable in Bethlehem two thousand years before, I felt that there was still promise of a regenerated world. The Angels had not sung in vain their wonderful hymn "Glory to God in the Highest and on Earth Peace, Good Will towards men".

Christmas has passed but I couldn't help reviving this thread when I read this by a man of the cloth and published in 1922.
Adrien