Anthem for Doomed Youth, Wilfred Owen
Probably the best known of the poets of the Great War, Owen was treated for shell shock at Craiglockhart, just a few moments from where I live in Edinburgh, where he met fellow poet Siegfried Sassoon (events fictionalised in Pat Barker's novel Regeneration and the film adaptation of the book). Owen was killed on November 4th, 1918, just a week before the Armistice. He was 25 years old; much of his poetry was published posthumously.
(the eternal flame and the tomb of the unknown soldier under the Arc de Triomphe; the legend reads "ici repose un soldat Francais, mort pour la patrie, 1914-1918. It stands in stark contrast to the more bombastic militarism of the Arc de Triomphe above it and the triumphant, processional way of the Champs Elyssee in front of it; the larger version is on my Flickr)