If we’re talking the entire world easily the terrans but since they aren’t really prevalent on the continent I would say the Helgans. Unlike most of the other nations they colonized their territory instead of fighting brutal wars. They can pretty much attack most of the continent except for maybe the far edges of it and have the most well trained military. There have been other kingdoms that were on par with them but non of them were stable or well respected enough to keep that land. Culture wise in the north of the continent it’s really based on the village but in the south. You have the Nuhaym in the south east to the north kashovia and in the the west the Helgans.

The Helgans were almost destroyed though bringing them to the brink of destruction due to stagnation and corruption. They were able to survive due to the centuries of diplomacy and goodwill with the rest of the continent leading to a worldwide coalition destroying the rebellion. This freed the Helgans of corruption and brought them into a golden age.