This is my crackpot theory about Natlan, before we get 4.8, which'll basically confirm it.
Everyone in Natlan is the Archon.
It's the Nation of War because while they're all the same person, they still vy for who the head is.
It's also why we've never seen anyone outside of Natlan.
Similar to what Focalor did, the goal of the Archon is to free itself from the concept of the Archon, so the people can be free. These proxy wars are in effect to find someone who can defy the will of Celestia.
Murata predates the Cataclysm, so she's long gone.
Previously, Murata prolly had the opposite approach, where her people went to other nations. But after dealing with slavery, the subsequent Archon no longer wanted that, so basically took another approach to the Sakoku Decree, rather than preventing people from leaving, simply give them no ambition to do so (because they're all them).
Saurians, being Dragons, are unaffected by this, but they're around cause of the Authority.
As others and myself speculated before, characters like Klee and Layla are Dragons, prolly from Saurians bloodlines dating way before the Cataclysm.
I'm definitely gonna be right.