A thousand years ago and some change, there was the magical equivalent of a nuclear holocaust. Superpowerful magic nations at war threw such powerful magics at each other that gods died, continents were destroyed or reshapen in blinks of an eye, and the whole fabric of reality holding the world together was shredded into thousands of pieces.
The world was broken into innumerable landscapes; miniature fragment planes of varying size, whose edges fade off in thick grey mist, which to enter is certain oblivion, passing into Unraveling. Some landscapes are nothing but forgotten ruins of the past, nests of unspeakable horrors created in the war, or empty scarred wastelands, the remnants of battlegrounds. Others hold survivors; isolated kingdoms, stranded farmsteads, wildlands with wandering nomads. Some hold the powers of the new age; groups which have retained or rediscovered the ability to build bridges across the mists, to jump across the planes, or to cross the veil into the unbroken Feywild or Shadowfell. You may all be from the same landscape, or from all different ones. You met, however, in no landscape at all… but rather in a prison, in the Shadowfell. For crimes, real or imagined, that you perpetrated against the people protected by the Architects of Imaskar, you were sentenced to banishment, and cast across the landscapes. You found yourself not in a random landscape across the world, however, but in a vampire fortress, across the veil where dawn never touches, kept like cattle as food.
In such bleak circumstances you met and became friends, and then, a cellmate slipped one of you a piece of paper. It was a Scroll of Recall; magic bound into writing which would return any who read its incantation aloud to the place at which it was written. A one-way escape ticket. While together for a meal, you used it, fleeing together somewhere unknown.