In the beginning, Vampires and Humans lived on the same land, the Vampires living to the east, and the Humans living to the west. Since times long forgotten, the Vampires had feasted upon the Humans as was their right to thrive off of the land.
However, unknown to the Vampires, just as they could summon the power of Demons of the Infernal Realm, so too, could the Humans access power from the Divine Realm. Using this power, the Humans appealed to their god Deus, who provided them with a miracle, splitting the land into two Crescents, in order to protect His chosen people from their grim fate.
This event was cataclysmic, and is believed to have killed two-thirds of the population of Terrasia. However, civilization found its way back, and the world was rebuilt in a new era.
Since then the Vampires have only lived on their Eastern Crescent, with no local sources of Humans, additionally, the secrets of summoning Infernal power was lost in the Shattering (though some Vampires have since rediscovered it, is a closely held secret among these Magi).
Without easy access to humans, and especially the after the rise of the Shattered Islanders, it soon became impossible to gain access to the luxury of Human blood.
But there are forces, working in the mist, to undo this curse upon Vampire-kind, who are doing all within their power to ensure that soon, for the first time in over a century, they shall be able to feast upon the blood of Humans yet again.