The scene along the Western Front is described in History.com:
At the first light of dawn on Christmas Day, some German soldiers emerged from their trenches and approached the Allied lines across no-man’s-land, calling out “Merry Christmas” in their enemies’ native tongues. At first, the Allied soldiers feared it was a trick, but seeing the Germans unarmed they climbed out of their trenches and shook hands with the enemy soldiers. The men exchanged presents of cigarettes and plum puddings and sang carols and songs. There was even a documented case of soldiers from opposing sides playing a good-natured game of soccer.
Merry Christmas from Portland.