There exist a fictional nation called Elf Nation. (not a creative name but this is for a grammar experiment)
The species which inhabit this nation are called elf(singular) and elves (plural).
Would the nationality of this nation be capitalized?
For example, in the real world, we would refer to a citizen of a nation as: American citizen or British citizen or Russian citizen and so on. We would capitalize the nationality and not the profession. More examples: Japanese writer, Chinese professor.
What if the adjective of our nation's citizens is the same as the species name. Would we capitalize the adjective then? Example from the real world: human astronaut, not Human astronaut
So, would we refer to a general of this fictional nation Elf Nation as: elf general or Elf general?
Also, would it be elf culture or Elf culture, seeing that we use human culture and not Human culture?
I know you could just make up a separate adjective in this case and a separate adjective already exists for this species. My question is mostly about if and when can you mix nationality and species if they are fundamentally the same.