Well you obviously don't have to read it to understand most things in LotR... I'm pretty sure you understand it all now, and you haven't read the Silmarillion
But if you'd like to dig deeper of course, you really should read it. It's one of many history books for Middle-earth and I highly recommend it. I mean, it'll help you understand
more about LotR of course and more clearly, because you'll be able to connect things and understand how certain things and people in the book work, why they're like that and why they're important.
Sorry my brain's been fried by the sun so I'm not making too much sense... hope you understand though
