Tolkien and mythologies

[vanwalossien]

I was a bit surprised that I couldn't find a thread about this yesterday, so I thought I'd just ask..

It is often mentioned that Tolkien created a mythology by mixing influences from many existing mythologies and other sources, in almost the same way as a real mythology gets created over a span of decades or centuries.

I only wondered if someone who is fortunate enough to know more than me about such things could tell me about what traces of "real" mythologies that can be found in Tolkien's writing, because I'm very fascinated with myths, but know embarrasingly little about them...