Found this amazing Wikipedia article about spontaneous truces breaking out amongst enemy units around Christmas of 1914 during WWI (and at other times). I love this idea of on-the-ground combatants exercising non-cooperation with war efforts… Maybe there’s a message for us today in this as well.
In the week leading up to 25 December, French, German and British soldiers crossed trenches to exchange seasonal greetings and talk. In some areas, men from both sides ventured into no man’s land on Christmas Eve and Christmas Day to mingle and exchange food and souvenirs. There were joint burial ceremonies and prisoner swaps, while several meetings ended in carol-singing. Men played games of football with one another, creating one of the most memorable images of the truce.
The truces were not unique to the Christmas period and reflected a mood of “live and let live”, where infantry close together would stop fighting and fraternise, engaging in conversation or bartering for cigarettes. In some sectors, there were occasional ceasefires to allow soldiers to go between the lines and recover wounded or dead comrades; in others, there was a tacit agreement not to shoot while men rested, exercised or worked in view of the enemy.
Truces between British and German units can be dated to early November 1914, around the time that the war of manoeuvre ended. Rations were brought up to the front line after dusk and soldiers on both sides noted a period of peace while they collected their food. By 1 December, a British soldier could record a friendly visit from a German sergeant one morning “to see how we were getting on”. Relations between French and German units were generally more tense but the same phenomenon began to emerge. In early December, a German surgeon recorded a regular half-hourly truce each evening to recover dead soldiers for burial, during which French and German soldiers exchanged newspapers. This behaviour was often challenged by officers; lieutenant Charles de Gaulle wrote on 7 December of the “lamentable” desire of French infantrymen to leave the enemy in peace, while the commander of 10th Army, Victor d’Urbal, wrote of the “unfortunate consequences” when men “become familiar with their neighbours opposite”.
This is also discussed somewhat in the “live and let live” page, also regarding WWI.