There's a Looper.com page dedicated to false ideas about Lord of the Rings, but it turns out one of their "corrections" is actually false.  Here's the page: http://www.looper.com/33552/false-facts-lord-rings-always-thought-true/  

To learn the truth, you'll want to read The Silmarillion: https://www.amazon.com/Silmarillion-J-R-R-Tolkien/dp/0544338014/ref=sr_1_1?ie=UTF8&qid=1486302061&sr=8-1&keywords=silmarillion