I dream about World War II way more than any other historical event. I mean, I've been on the Titanic and I've fought in Vietnam and I've seen Caesar assassinated, but more often than not, if there's history involved, I'm running from Nazis.
As dreams often go, the Nazis are mashed up with other stuff (Sunday night was Harry Potter/X-Files/WWII dream), but even if Bill Clinton is president and werewolves are attacking the White House, Hitler is going to turn up somewhere.
I blame the over-saturation of our media with Hitler/Nazi references. I also hate that I dream about it so much because it makes me feel like I am one of those Fox News reporters who somehow turns everything into "Well, you know how this kind of thing went down in Germany in 1939." But I suppose it's not my fault. If I could control my dreams, I'd have even more about my cats doing awesome stuff than I do now. Like the dream where Fidel was swimming around and doing tricks in the bathtub. Way better than the Gestapo killing Dumbledore AND Agent Scully. And Neville of all people was a double agent? We were doomed from the beginning.