World War I Bombing Prank:

During the early days of World War I, the interactions between the warring sides tended to be civil. In fact, for the first Christmas of the war, the opposing sides on the Western Front paused hostilities in order to exchange gifts. Thus, it should be expected that 3 months later, there would be pranks. On April Fools’ Day 1915, French pilots “bombed” German soldiers, except the bombs were just footballs with notes tied to them. What did the notes say? “APRIL FOOL!”