On Zetacron, the nature goddess Gaia did not create the elves, but wished to claim them as Her own (it seemed fitting to her, somehow, that elves should be bound to Nature). Thus, she used her divine powers to create a bond between Herself and the elves.
Context: The gods of Zetacron are physically present in the world. You can go and meet them if you like. Additionally, they are very human, with flaws and quirks—possibly more than regular people.
Want to avoid fighter types focusing on swords? Make Longswords and Bastardswords the weapon of the Noble class, with a death penalty for other to carry. These weapons will be ornate and finally crafted. Adventurers will be stuck with cheaply made broad and shortswords, while professional fighters might use two handed swords.