When the war started, John McCrae was appointed medical officer of the First Brigade. He was involved in the Second Battle of Ypres and treated the wounded. He was eventually ordered away to set up the No.3 Canadian General Hospital where he stayed for the rest of the war. Soon after, he wrote one of the best known poems in the war called "In Flanders Fields".
John McCrae died on January 28, 1918 from pneumonia while still commanding the field hospital.
He was inspired to write his famous poem after a funeral of his friend and fellow soldier.
For 8 months, the hospital John McCrae worked in was operating in tents.