Ryndaria is a continent under constant war. The Final War, as it was dubbed by those who began it centuries ago, has raged on, destroying countless kingdoms, and making many parts of Ryndaria completely uninhabitable. Through the carnage, two human superpowers have risen up: Greystone and Nexora. Though these two human kingdoms are in constant battle with one another, a stalemate has arisen. The military complex feeding the war has led to both kingdoms seeing increased wealth and prosperity.
The other races (elves, dwarves, halflings, the Lunatio, and others) have either retreated into smaller and smaller lands, or been forced into service to the human kingdoms.
The elves stay on the west side of the central mountain range. They live in Nemus Forest. Few elves roam the lands of the humans any more.
The dwarves have completely retreated into the UnderCities. While they are still willing to trade with humans, they usually do business through intermediaries like the goliaths.
The halflings’ home land was utterly destroyed and turned into The Waste Lands decades ago. Halflings are forced to live in slums of human towns or to become servants to wealthy humans for the most part.
The goliaths stay in the hills and mountains, usually acting as middlemen in trade between dwarf and human.
The Lunatio, a wolf-like shamanic race, stay on their island home of Moonwell. Very rarely are they seen on the greater continent.
Most custom races in D&D would exist somewhere in the land of Ryndaria, but many would be extremely limited in number. A player playing many of these races (especially monster races and those from alternate planes), would be extremely unwelcome in the human kingdoms. Players known to travel with such races would be equally ostracized.
The world’s focus is always on war, yet the needs of the war have led to great advances in magic and technology. Magical and superior equipment is becoming more readily available every day, though those with the knowledge and ability to create these items can become wealthy very quickly and so guard their secrets. Competition between merchants and magicians usually lead to the unfortunate death of the lesser competitor.