[@ASTA] There's a map on page 39. All the grey nations are unoccupied.

A few notes, though:

Britain mentioned that they wanted to take control of Canada, so that might be considered taken already.

Iran, while not technically apart of any player's nation, was invaded by South Asian forces. It's also been heavily influenced by the Caliphate, it's neighbor. So those would be things to keep in mind if you wanted to sign up as Iran.

The Caliphate is looking to add Saudi Arabia into it's fold, so that's probably out too.

I've already signed up for Spain so don't you dare take that away from me.

I think that might be it. But, yeah. The southern nations of Africa are mostly open, Norway is open, some countries to the east of India are open, and Brazil and its neighbors are open.