The ceasefire began with the sound of singing on the battlefield. It was Christmas Eve 1914, along the Western Front of the fighting in WWI. German soldiers alternated singing Christmas carols with their enemies—British, Belgian, and French soldiers. This goodwill spilled into the next day, when fighters emerged from the trenches, unarmed. They introduced themselves and exchanged small gifts. Reflecting on that experience, one veteran said, “If we had been left to ourselves there would never have been another shot fired.” A short break in hostility allowed the soldiers to see their opponents as people, not merely enemies.