Though much of the World War I movie 1917 is fiction, it is loosely based on an account that director Sam Mendes' paternal grandfather, Alfred Mendes, told to him when he was a boy. Mendes described his grandfather's story during a Variety podcast, stating, "I had a story that was a fragment told to me by my grandfather, who fought in the First World War. It's the story of a messenger who has a message to carry. And that's all I can say. It lodged with me as a child, this story or this fragment, and obviously I've enlarged it and changed it significantly. But it has that at its core." It turns out Mendes' grandfather was the messenger in question. -The Times
Born on the Caribbean Island of Trinidad, Mendes' grandfather, Alfred, left for England in 1915 and joined the British Army, enlisting in January 1916 at age 19. After serving with the 1st Battalion Rifle Brigade, he was sent to Oisemont, not far from Dieppe, France, where he trained to be a signaller. He was then sent to the Battle of Passchendaele in Belgium. On October 12, 1917, hundreds of British soldiers, including Alfred Mendes, were tasked with reclaiming the village of Poelcappelle, which is close to the Passchendaele Ridge and had been overtaken by the Germans. British soldiers attacked in the pouring rain and suffered significant losses. 158 of the 484 men in Alfred's battalion were killed, wounded, or unaccounted for. The missing men were scattered across miles of water-filled shell craters in the mud-soaked No Man's Land, unable to communicate their positions.
No. The 1917 true story reveals that, at best, Dean-Charles Chapman's character, Blake, was very loosely inspired by Sam Mendes' grandfather, Alfred Mendes. Blake's friend in the film, Schofield (George MacKay), also perhaps loosely represents Alfred's experience during the war, but neither character is directly based on Alfred Mendes. In the 1917 movie, the pair are given the mission of crossing deep into enemy territory to get a message to 1,500 soldiers who are unknowingly headed into a deadly trap, including Blake's own brother (portrayed by Richard Madden).
No, we've found no evidence that they represent real people. The supporting characters in the 1917 movie, including the commanding officer portrayed by Colin Firth and the characters portrayed by Benedict Cumberbatch, Richard Madden and Mark Strong, all appear to be fictional.
The movie opens just after the German army purposely fell back to the Hindenburg Line, which was shorter and easier to defend. This real-life strategic withdrawal was known as Operation Alberich. In the mostly fictional movie, the Second Battalion of the Devonshire Regiment mistakenly believes that the Germans are in retreat. The battalion is preparing to attack without knowing that the Germans are waiting to overwhelm them. With the lines of communication cut, two British soldiers are tasked with hand-delivering a message to call off the attack.
The fighting in the movie was inspired by (but unfolds prior to) the Battle of Passchendaele, also known as the Third Battle of Ypres, which took place from July 31, 1917 to November 10, 1917. Both the British and the Germans suffered heavy casualties. In the end, the battle resulted in the German army being pinned to Flanders and suffering unsustainable casualties. As stated earlier, Alfred Mendes fought in the battle, and his battalion suffered heavy losses while trying to take the village of Poelcappelle from the Germans.