Extra Kingdom, they exist because I can’t think of anything, directly from The Battle of War 2, one of the most competent, democratic, and well run nations, the monarch is mostly ceremonial at this point, one of a handful or superpowers.
They are a federation, each island being a unit with it's own government, they hold regular elections, but the king is technically in charge, though they usually leave it up to the governors.
Despite being really near to the Frozen Wastes, they are a beast, their capital is among the top 10 biggest cities, and shockingly, there aren't many neanderthals, the leading theory is that because they are islands, and really remote, neanderthals just never made it there before humans boated there.
In order of population:
Extra Island
Unnamed Island
Boom Island
Enchanted Island
Pupia
The capital is named Extra City, by the way.
Enchanted Island is well known to be really crazy, with a WILD ecosystem,and extremely lush, bright green flora, home to many fairies.