From watching old WW2 movies as a kid I thought Germans (in Germany) spoke English with a German accent, Japanese spoke English with a Japanese accent and so on.
A childhood belief about foreign languages

others believed things like this
- I used to think that even people who spoke something other than English, thought in English— Peaches
- Since Germans speak German, I thought Jewish people spoke Jewish.— Lori
- I used to believe that, no matter what language other people spoke, that everyone thought in EnglishAnon
- I used to believe that everybody spoke English in the worldAnon
- I used to believe that if I spoke with whatever accent a language was in, I was speaking that language...— Renae
- I know my dog, Palmer, spoke English, he was just really quiet.
— Klayne P.