Call it a theory, but I am becoming more and more convinced that World War Two has been used as a backdrop for movies more than any other event in human history (perhaps because it occurred right around when movies really become a cultural phenomenon, not to mention the fact that Nazis never fail to make effective villains).
There have been so many of these movies that I have a timeline in my head (similar to the ones you would find about the MCU online) where certain stories (fictional or not) are being played, be it Dunkirk (2017), Saving Private Ryan (1998), Casablanca (1942), Grave of the Fireflies (1988), The King’s Speech (2010), Empire of the Sun (1987), Come and See (1985), JoJo Rabbit (2019), or Inglorious Basterds (2009) (the latter two being in an alternative universe). That does not even account for films about the Holocaust (which I would argue is a separate event).