I used to think (for an alarmingly long time, well into my teens) that the very last to words to "My Country "Tis of Thee" were "and from every mountainside, let free Yombre" (let freedom ring). Now I had no idea who Yombre was or in which particular mountains he was being incarcerated, but this was AMERICA DAMMIT! and LET FREE YOMBRE!
A childhood belief about misheard lyrics

others believed things like this
- When I first heard Matt Monro's song "Born Free," I thought he was singing "Porn Free."Anon
- When i was a tiny lad, I used to think drug free zones were places where you can get drugs for free— Spencer
- I used to think that money from ATM machines were free :p— qwerty
- I used to believe that priceless meant free.— Neo
- I used to think that "priceless" meant free.— DAAA
- That everything was free. You paid for nothing, money was just to look nice.— Blasia M