Hastur

Hastur (The Unspeakable One, Him Who Is Not to be Named, Assatur, Xastur, H'aaztre, or Kaiwan) is an entity of the Cthulhu Mythos. Hastur first appeared in Ambrose Bierce's short story "Haïta the Shepherd" (1893) as a benign god of shepherds. Hastur is briefly mentioned in H.P. Lovecraft's The Whisperer in Darkness; previously, Robert W. Chambers had used the name in his own stories to represent both a person and a place associated with the names of several stars, including Aldebaran.

In Bierce's "Haïta the Shepherd", which appeared in the collection Can Such Things Be?, Hastur is more benevolent than he would later appear in August Derleth's mythos stories. Another story in the same collection ("An Inhabitant of Carcosa") referred to the place "Carcosa" and a person "Hali", names which later authors were to associate with Hastur.

In Chambers' The King in Yellow (1895), a collection some of which are horror stories, Hastur is the name of a potentially supernatural character (in "The Demoiselle D'Ys"), a place (in "The Repairer of Reputations"), and mentioned without explanation in "The Yellow Sign". The latter two stories also mentioned Carcosa, Hali, Aldebaran, and the Hyades, along with a "Yellow Sign" and a play called The King in Yellow.

H. P. Lovecraft read Chambers' book in early 1927 and was so enchanted by it that he added elements of it to his own creations. There are two places in Lovecraft's own writings in which Hastur is mentioned:

I found myself faced by names and terms that I had heard elsewhere in the most hideous of connections—Yuggoth, Great Cthulhu, Tsathoggua, Yog-Sothoth, R'lyeh, Nyarlathotep, Azathoth, Hastur, Yian, Leng, the Lake of Hali, Bethmoora, the Yellow Sign, L’mur-Kathulos, Bran and the Magnum Innominandum—and was drawn back through nameless aeons and inconceivable dimensions to worlds of elder, outer entity at which the crazed author of the Necronomicon had only guessed in the vaguest way.... There is a whole secret cult of evil men (a man of your mystical erudition will understand me when I link them with Hastur and the Yellow Sign) devoted to the purpose of tracking them down and injuring them on behalf of the monstrous powers from other dimensions. —H. P. Lovecraft, "The Whisperer in Darkness"

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