In a previous Age, the great wizards of that Age created giant golems for some unknown purpose. And then they lost control of them. These golems, called Shambles for their slow, shuffling gait, began to wander the world. They left only destruction in their wake. In short order, little remained of that Age. The Shambles had trampled it all underfoot.
The only place of refuge for most was atop the very creatures that had ended civilization. Cities were built atop the Shambles. Druids were tasked with creating arable land and forest to save as much of the lifecycle as they could. Much knowledge was lost to time or the step of a Shamble's foot.
Centuries have passed.
Life has stabilized. Dwarves, who had retreated to their mines, reemerged, but as slaves to the dark elves. Surface elves, doomed to never again know the shade and comfort of a forest, Mourn each of their births. Barbaric tribes roam the Wastes and subsist on what they can snatch in their raids on the Shambling cities. Magic users, hated for their perceived involvement in the creation of the Shambles, hide their abilities from most.
Some refuse the idea that the golems are creatures of destruction. Acolytes of the Ark believe the golems, which they call Arks, were created for the purpose of saving the people of the world. Many find "Arkers" beliefs laughable, but some find the idea that they were saved from a worse fate comforting.
For the adventurer, the world of Vernlarum holds great promise. Out there in the Wastes, lie the remains of the Ruiner civilization that birthed the Shambles. Every story about the Ruiners and their magical wealth is grander than the last. Raiders are a constant threat to the Shambling Cities, so adventurers who aid a city are appreciated and sometimes even beloved. War between cities is rare, but not unknown. And rumors abound that the City of Mandith seeks to expand to other Shambles.