A physician and army officer, McCrae wrote the poem during the Second Battle of Ypres in the spring of 1915, the day after the death of his good friend, Alexis Helmer, who was killed in action.
The verse was subsequently published and McCrae became a famous poet but continued to work as a surgeon on the front lines of the war.
His poem is recited annually at Remembrance Day ceremonies around the world. He is also credited with the idea of adopting the poppy as the official flower of remembrance.
(image by Wazimu0 via flickr)