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Originally Armistice Day, this is 11 November in the United Kingdom and the British Commonwealth. On this date, the end of World War I and the fallen soldiers of that conflict and others are commemorated and remembered. It is the tradition on that day to wear a red poppy to commemorate the poppy fields that now grow over the battlefields of France and Belgium.
France and Belgium also observe Remembrance Day, with the French using the blue cornflower (the bleuet de France) in place of the poppy. The United States also celebrates the same day as Veterans Day, honoring all military veterans.