Likenesses in Middle Earth

I suppose this can be found in the movies as well as the books, but, I've noticed that certain civilizations in ME correlate with civilizations of the world. For example, Rohan seems to be a much more Nordic, Scandinavian state. It could be guessed that Tolkein designed it after his studies of Beowulf. Minas Tirith has a more regal, Roman feel to it. What are your thoughts?