The unofficial Christmas Truce began with carols on Christmas Eve and reached its height on December 25, when informal ceasefires, joint burial parties, and even a few reported football matches spread along stretches of the Western Front. Soldiers who days earlier had been trying to kill one another exchanged tobacco, buttons, and songs, an episode commanders on both sides moved quickly to stamp out in subsequent years.
The truce was never ordered by any high command; it emerged spontaneously from exhausted, freezing men in trenches sometimes only 30 yards apart. Carols started it in many sectors — British troops reported hearing German soldiers singing 'Stille Nacht' on Christmas Eve and responding with 'The First Noel,' the songs carrying easily across the frozen, cratered ground of no-man's-land.
By Christmas Day, in numerous sectors, men climbed out of their trenches unarmed to meet enemies face to face for the first time, exchanging small gifts of cigarettes, buttons, and cap badges, and using the lull to bury bodies that had lain unclaimed for weeks. A handful of units organized impromptu games, though the popular image of a full organized football match against a German team is likely exaggerated in most accounts, based more on scattered, small-scale kickabouts.
High command on both sides was furious when word got out, fearing it would sap the troops' willingness to kill. Strict orders against fraternization followed, and nothing on this scale was ever repeated in later Christmases of the war. For one day, though, tens of thousands of men across a war of unprecedented industrial slaughter chose, briefly, not to fight.