In 1914 during World War I the opposing armies put down their weapons and joined each other to celebrate Christmas. This happened in several places along the front lines, and in at least one case the soldiers refused to go back to war and had to be replaced. If you want to read more about this, you can find partial information on the snopes site and elsewhere on the web. The solders who first walked across the "no man's land" between the trenches and extending their hands to the enemy were risking their lives. But the result was there was peace. And the peace didn't end because arguing broke out between soldiers. In some cases the soldiers had to be replaced, and in others they only resumed fighting after persistent orders from officers.