"In Flanders fields the poppies blow
Between the crosses, row on row,
That mark our place; and in the sky
The larks, still bravely singing, fly"
"In Flanders Fields" was written during World War I by Canadian officer John McCrae. Today, it's one of the most famous, internationally-revered poems about war. And its description of poppies blooming along soldiers' graves gave way for the red poppy flower to become the "Flower of Remembrance" for veterans all over the world.
In the U.K., people wear poppy lapels and place the flowers on veterans' graves to celebrate Remembrance Sunday.
In the U.S., the "Buddy Poppy" is the official memorial flower of the Veterans of Foreign Wars. Each year, the VFW sells roughly 14 million of them worldwide, and profits from the sales go to veterans and their families. The flowers themselves are made by veterans as a source of income and art therapy.
Though the symbolism of the poppy is rooted in warfare, the Royal British Legion — a U.K. charity for veterans — says the flower is not a symbol of death or a sign of support for war.
For some people, however, the poppy can still be a painful reminder of bombings and destruction.
Manchester United player Nemanja Matic is choosing not to wear a poppy during a game on Remembrance Sunday, because it reminds him of bombings he experienced as a child in Serbia.
On Instagram, the athlete wrote: "I do not want to undermine the poppy as a symbol of pride within Britain .... however, we are all a product of our own upbringing and this is a personal choice for the reasons outlined."