Ok, me and my friends used to have this strange belief that a knights rank was determined by the spikey-ness of his helmet. I recall one of my arguments with my friend ending with: "MY HELMET IS SPIKIER THEN YOURS, SO THERE!"
A childhood belief about history

others believed things like this
- that DOT was a particularly popular brand of motor cycle helmet.— Gary Watrous
- I thought that there was a law that all movies had to have a happy ending— Quatsch
- I used to think Russians had surnames ending with ski because of the skiing they do in Siberia.Anon
- I thought that Loch Ness was actually Loch Nest because it was like the monster's nest— Dietrich Corby
- I thought my age started at 4, because I couldn't recall any mention of my age before.Anon
- I used to belive that however many pieces of cake you had determined how old you were turning!Anon