Holy crap i hop you are trolling. I do not remember exact dates/years but someone correct me if im wrong the LOTR books were from late 1930's- the 1940's? I remember reading about some of the Stuff was made by Tolkien was heavily influenced by WW2
Actually Tolkein served in the British army during WWI, not WWII.
But both wars had a profound influence on Tolkein's worldview and on his mythology. For instance, his world is one that is under the constant threat of war, and when wars breakout they result in permanent, irrevocable, and profound changes to the world. In real life.
WWI and II resulted in the fall of empires that had lasted for centuries and the creation of completely new nations (goodbye Holy Roman Empire and Prussia, hello the Bundesrepublik and the Volksrepublik). Likewise, the end of the war with Sauron spelled the end of the Third Age, and almost all the elves left Middle Earth.
To be fair all Tolkien did in turn was take Norse and Celtic myths, throw them in with some Quasi-Abrahamic allegories and put his own spin on it all.
I more or less agree with you. However, at least a lot of the results of this synthesis were completely novel and completely Tolkein's, and fantasy archetypes can be directly linked to Tolkein's work. However, before Tolkein's work, there were many conceptions for what "elves" were: divine or semi-divine beings, dangerous tricksters, something akin to fairys or pixies, etc. Tolkein hammered out the details of what "elves" were in his universe, and elves in most fantasy after him were quite similar to his.
And don't forget the hobbits--they were completely his creation with little precedent. They became the halflings of many fantasy settings.