@Kaarme I get the feeling. I had to check the manga again to understand the situation. As far as I can remember:
Fonclanc: The country Yuusuke is working for right now. Ruled by king Esvobus, father of Violet, the twin-tailed princess. Divine artists are the elite, but things aren't as bad for the powerless as in other countries. Most of the cast are from Fonclanc, including Sun, the entire Dark God Squad, Kreivol (the princess' assistant), Hivodir (a fiancé candidate for the princess) and old master Zeshald.
Gazetta: The only country where the powerless rule. Shinha, the big white-haired guy, is their king. The loli grandma, Ayuukas, is also from there.
Blue Garden: A neighbouring country ruled by divine artists. Thanks to Yuusuke's intervention, queen Rishaleus (who was also Shinha's childhood friend) now rules it without being a puppet of a rather warmongering faction. Reifold, the shady spy, seems to be from Blue Garden... but he also seems to be working for several factions at the same time.
Nossentes: Another artist-ruled country, their Divine Council tried to use song princesses like Lasanaasha and Laazasshia to manipulate and get rid of Yuusuke, as well as other agents to cause trouble to their neighbours. In the end, they were destroyed by Gazetta and there was much rejoicing.
Trentrietta: The last country Yuusuke has visited (all the issues about the glowing moss and the monster facility). In this chapter they're said to be mostly pacifists and hedonists, except that House Elfodras that may be involved in a conspiracy about that facility.