Piety and Poison
The Umbral Sisterhood, also known as the Sisterhood of the Silent Veil, is a long-dead faction of defenders of the Nentir Vale. Their brief was to protect the Vale from incursions from the Shadowfell and were specialized in fighting the undead.
The sisterhood was established by a druidess named Jashendra the Wise in the year -328 AE, two years after she discovered the source of the undead menaces that plagued the southwestern foothills of the Dawnforge Mountains. The source was a small, but incredibly malign and recurring Shadow Rift beneath the Blackened Hills.
In the year -326 AE, Mistkeep Abbey was constructed over the site of the rift. The purpose of this was threefold: To guard against further undead incursion, to maintain magical warding upon it to limit its size, and also to use the rift as a training grounds for the Sisterhood.
For over a hundred years, the Sisterhood fought undead throughout the Vale, and became a crucial part of the Nerathian Empire’s efforts to protect the troubled region against the unusually frequent breaches in the barrier between worlds.
Then, in the year -205 AE, the abbey came under siege by the undead forces of the lich known only as Lord Dust. The abbey held strong against the initial attack, but the Sisterhood was not aware that it was simply the expeditionary force of Lord Dust’s legion. It is probably no coincidence that this was the same year as the appearance of the Cairngorn Shadow Rift. Before the year was out, the abbey was destroyed in a cataclysmic attack, waves of undead boiling from deep within the earth to consume the Sisterhood and scatter its few survivors.
It is believed that all of the Sisterhood’s leaders were killed or converted in the attack, for the legacy of the Sisterhood was destroyed along with the Mistkeep Abbey, never to reform.