A History of the Werld
This world, known as Werld to astral travelers and spelljammers, is a temperate planet a little smaller than Earth but with the same physics and climate etc because Magic. It orbits a yellow sun known as The Sun and has one satellite known as The Moon. The Moon is speculated to contain labyrinths, demons, eldritch temples, and so forth, but nobody from Werld has been there yet.
Civilization arose in the land of Parz about 10,000 years ago. Parzian culture spread to Saien to the north and Hafer to the west but was mostly ignored by the cave-dwelling barbarians living elsewhere. Eventually Parz did what all great ancient world cultures do, they delved into forbidden magic they could not control and, failing to check themselves, wrecked themselves.
About 5,000 years ago, Parzian culture and philosophy was rediscovered by the city-state of Mez on the north shore of the Mezzoterranian Sea. They proceeded to form a great and prosperous republic with their neighboring city-states, and maintained friendly relations with the elves of Suprora to the west, and eventually Mez did what all great ancient republics do, they turned into a conquering empire. They siezed holdings in Hafer, retook the coastal cities of Parz, established a thriving presence on the wild and primordial island of Bload, and pushed against the borders of the great nation of Saien, but they could never gain a foothold to the northern countries of Engol and Jerma, where dwarves and orcs and savage men fought off their incursions.
However, about 1,000 years ago, the emperor Panseres succeeded in bringing Engol and Jerma to heel. His triumphs and popularity earned him many enemies in Mez, and he spent his final years ruling from the ancient castle of Engolan kings at Tar-Eng. When he died, a succession of incompetent rulers left the Mezan Empire weakened, and eventually they did what all aging empires do, they got overrun by raiding tribes of horsemen and orcs and goblin hordes, and over the next few hundred years local rule was restored to all of their colonies.
Currently, Engol is ruled by the High King at Tar-Eng. The great elven forest of Suprora on the southwest peninsula is technically part of Engol, but self-governs. Jerma's government is a confederacy of orcish tribes led by a Supreme Overlord, dwarven nations ruled by a Grand Council, and a High King of the human holdings. There are elves in Jerma but they have opted out of this arrangement. What once was the original Mezian Republic consists of a large number of small, warring city-states ruled by warlords and princelings. The original city-state of Mez is mostly ruins and is currently the stronghold of an archmage. Bload has been under the rule of a demented lich since shortly after the death of Panseres.
The kingdoms of Hafer are prosperous and engage in trade with the northern countries, but significant cultural exchanges have been few and far between since the fall of Mez. Saien is a vast and technologically advanced empire in its own right at this point, but keeps itself largely isolated. It it believed to have established colonies in Parz, which has not been visited by the western countries in many years, and of which little is presently known.
Update: here's a rough map of the world.