How can I tell what nation I am?

[Mango]

I know, I'm a goofball. I read about choosing a nation but I don't remember seeing that option when I started the game. Did I choose and not realize or do I choose later in the game? Thanks!!!

 

[Isekai]

You unlock a nation as u progress, I think it was then iron age you choose.

 

[Mango]

Great, thanks! I thought it might've been something like that or I really missed the boat.