When I was about 4, my dad thought it would be a good idea to teach me about my ancestors. Apparently they were a Norwegian clan of vikings (true story). He worded it incorrectly and said, "We used to be vikings up north where it's cold".
I spent the next year thinking that, even though I could remember it, I used to be a viking savage from Alaska.
A childhood belief about i'm different

others believed things like this
- I used to thing that vikings lived 50 years ago.— Sigrid
- When I was 5 years old, I used to believe Poland was snowy and cold all year round, like the North Pole. — Sara
- I used to believe that the cold war was happening in Siberia or Alaska.— Liam
- i thought that when you die they retire your email adress (apparently it's not true)— Nanofreak
- I used to think that my cat was an alien that had come to teach me how to be good!— laz
- I used to think that when a movie was 'based on a true story' it was happening for real then and there— Tom