Actually, I think the early part of World War II is more of an influence -- certainly structurally, which is the great flaw of the myth in the books (apart from the dreary prose style). World War II (from the British angle) was about the threat to the little hobbit isle by the spread of Nazism. Unfortunately for the books, it sets up this weird situation where the final battle takes place on the homeland of the evil being, when by the dynamic of the tale, it should happen in the shire, with everyone's back against the wall. Everyone in the books keeps saying that our back is against the wall, but they keep moving forward into enemy territory. Throughout the books it is Sauron and Saruman who are threatened and embattled, in spite of the rhetoric of doom, evil spreading, etc.
yours,

Peter T.