The history of the Blood of Vol is little known. Unlike Vassals or Purified, Seekers do not see their faith as explaining the fundamental mythology of the world. The disjointed and individualistic nature of worship reinforces this, leaving the true history of the faith a mystery.
Ancient History
Long ago, the Qabalrin elves of Xen'drik mastered the necromantic arts. While their civilization in the Ring of Storms has not survived, their use of undeath as a form of immortality persisted into the elven emigration to Aerenal.
The Line of Vol
On Aerenal, the line of Vol arose as political rivals to the Undying Court. The family and its allies drew upon the power of Mabar to create undead, taking from the living rather than relying on devotion like the Court. The Court's ties to Irian made them natural enemies, a tension that only grew when the line of Vol developed the Mark of Death.
The creation of the half-dragon Erandis Vol was a line too far gone. The Undying Court acted in concert with the dragons of Argonnessen to end the threat, killing not only Erandis but every elf who shared her bloodline. This unprecedented purge of political rivals led many elves to flee the island. Some traveled to mainland Khorvaire, while others fled to the Lhazaar Principalities. Minara Vol and her families close allies fled to Farlnen, forming the basis of the Grim and the Bloodsails.
The Faith spreads in Khorvaire
The exiled elven necromancers shared their story with their new human neighbors - that "the heroic family of Vol had sought to attain godhood, only to be destroyed by the jealous gods." This telling was especially popular where cruel warlords propheted the empty promises of the Sovereign. While the elven necromancers drew upon purely the power of Mabar and saw undeath as immortality enough, the newfound Blood of Vol sought something more - the Divinity Within. To the surprise of the elves, these new clerics found divine power.
While Seekers can be found anywhere in Khorvaire, the faith has always been associated with Karrnath. Not only did the land's harsh climate foster belief that the gods were cruel and uncaring, but the faith actually transformed the Mabaran manifest zones of the nation from a blight into a resource.
The Last War
Early in the Last War, Karrnath's overwhelming military might was held back by famines and plagues at home. Seekers today point out that some of the warlords of Karrnath turned temples and towns devoted to the Blood of Vol into military garrisons, heedless of the rituals and practices meant to contain Mabaran manifest zones. Many Karrns though believe the official proclamations of Moranna and Kaius III, that the plagues and famines were engineered by the leaders of the faith to force Karrnath to accept it as the state religion.
The truth of the matter is difficult to ascertain given Lady Illmarrow's secretive involvement. Erandis Vol forced Kaius to not only accept the Blood of Vol as the state religion (See the "Hierarchy" section), but turned the power-hungry king into a vampire.
Once established as the state religion in 897 YK, the Blood of Vol not only addressed the abundance of disease and shortage of food, but equipped the Karrnathi army with the first major technological development of the war - the widespread use of undead. The then-living Malevanor worked with Gyrnar Shult to create the Odakyr Rites to create more capable undead out of the corpses of Karrnathi patriots.
This all began to fall apart in 976 YK, when Regent Moranna outlawed the Order of the Emerald Claw. She presented evidence of the order's crimes and seized their strongholds and arrested its leaders. While Moranna was not the most popular ruler for these actions, Kaius' III trend of decreasing the influence of the religion in Karrnath removed it from its official status entirely.