The Old World

The most favoured theory of how the current world was formed is known as "Old World Theory". It claims that, before the world's continents took on their current shape, they were organised in a much more "orderly" fashion that allowed for the rise of the different races.
The "Old World" would have been comprised of four continents: the North Continent, the South Continent, the East Continent, and the West Continent, which a sizeable archipelago in the middle. Each of the world's main race would have flourished in one continent.
Explanations of why the world took on such a shape go from the extremely religious (the gods willed so) to the magical (the planet willed so) and to the "scientific" (the random movement of tectonic plates did a wonderful job entirely by chance). It is precisely because of this flexibility that the "Old World Theory" is still the most accepted idea of the origin of the world.

Summary

The Old World Theory claims that humans were the first race to develop. Humans consider it a point of pride, but other races just think it is because humans are the weakest and everything that came later was an improvement. Whichever the case may be, the consensus is that Humanity grew the first great civilisations in this Central Archipelago before spreading its wings to the rest of the word.
Firstly, the humans headed east and found a continent dominated by harsh desert lands. They also found magical animals that when eaten enabled people to experience a world beyond what their normal eyes could see. Bites of those animals spread a deadly disease that killed 90% of those affected. The survivors, however, gained the permanent ability to see the world beyond (as well as a third eye in their forehead). Those were the first sorcerers.
When humanity (and sorcerers) spread west, they found endless jungle. Sorcerers studied studied the local species and used their knowledge of the world beyond to turn some humans into a brand new species capable of thriving in such an environment: the elves.
Humanity then went south. The land was dominated by ice and darkness. Sorcerers once again helped humans speed up their adaptation to the new environment, and the first werewolves came into the world.
Lastly, humans went north. Again they found cold and darkness, but also tundra, pine forests, and the tallest mountains they had ever seen. When sorcerers tried to make humans able to thrive in this environment, they did not know that in a few thousand years their creation would turn against them and everyone else. Vampires never intended on staying in the frozen forests for long...