The H.P. Lovecraft Wiki

This subject contains information from the "Lovecraft Circle" Myth Cycles, and while guided by HPL are not based on his work alone. The Darkness is an Outer God, and the progenitor of Shub-Niggurath.

Behind the Mythos

Lovecraft mentioned the Nameless Mist in a family tree of Cthulhu he jokingly wrote in a letter.

The Magnum Innominandum and The Nameless Mist were unified as the same entity later by other writers, notably by Lin Carter and by the Call of Cthulhu RPG (some readers still believe the Magnum Innominandum to be a term for Yog-Sothoth). For this reason, Darkness is sometimes known as "Magnum Tenebrosum" or "The Unnamed Darkness" as a parallel to its sibling.

In the The Dream-Quest of Unknown Kadath, Randolph Carter is described as falling through endless voids of "sentient blackness". It's unknown if this is related to the entity named Darkness, though much of the language used to describe the realms outside of existence such as the Ultimate Void and the Court of Azathoth relates to blacknesses, darkness, "spiral black-vortices" and such (it is also note mentioning that the Ultimate Gods are described as "tenebrous").

Lovecraft's tongue in cheek family tree: (HPL: Selected Letters of H. P. Lovecraft 4.617)

            /                          /                                  /
      Nyarlathotep            The Nameless Mist                       Darkness
(The ancient patrician                 /                                  /
gens Viburnia of Haec                 /                                  /
RESPVLICA.ROMANA)                Yog-Sothoth------------+---------Shub-Niggurath
            /                                          /
           /                              ____________/___________________
   L. Viburnius Marco                    /                               /
            /                           Nug                             Yeb
           /                             /                               /
   P. Viburnius Marco                   /                               /
    Legatus of Legio 11.,            Cthulhu*                       Tsathoggua*
    station'd at Isca Silurum,           /                               /
    in Britannia Secunda                /                               /
    in A. D. 103                    Shaurash-ho                        Yabou
            /                           /                               /
           /                           /                               /
          /                     Yogash the Ghoul                 Nush the Eternal
         /                              /                               /
        /                              /                               /
       /                        K'baa the Serpent                Gilles Grenier,
      /                                 /                       Lord of Averoigne
     /              **                 /                                /
 Viburnia-----------+-----------Ghoth the Burrower                     /
                   /        (one of the Little People)        Hippolyte Le Sorcier,
                  /                                             ancestor of
          Llunwy of Wales                                       Clark Ashton Smith
            ancestor of
            Owen Gwynedd
            and of H.P.L.

* First of their respective lines to inhabit this planet.
** This union was an hellish and nameless tragedy.