Note also that by the time the Russian Revolution happened, Dracula had been published for roughly two decades.
Dracula - 1897
Tunguska - 1908
Russian Revolution - 1917
True Pietrovich's letters mention it as early as 1902 where he talks about publishing it further, with a previous mention of him instructing the Orthodox Church in eliminating Black Court Vamps.
ok to go in depth of the full theory which I guess is mine, if no one else claims it is this.
Kemmler developed the Dark Hallow through a mixture of Necromancy and Ancient Ritual Spell which reportedly Hecate, A Winter Queen, the Erlking all used to ascend and which Dracula attempted to copy so he'd be on equal terms with Daddy Dearest Drakul.
The Black Court Elders after a decade of the purge due to the macchinations of the White Court who inspired by Mabs use of the Grimms to keep Faeries relevent used it for opposite purpose and wrote an instruction manual on how to kill them after which Lara sexed Stoker to death before he could write a sequel.
The Black Court Elders gather at Tunguska to perform the Dark Hallow using the Necromantic energy of the Black COurt but perhaps missing the key ingredient of millions of human life.
Ebenezar getting word of the ritual (probably from Simon) creates Tunguska possibly with help from the Brute Squad assault team. Interesting to note that 1908 is also the year of the first failed Russian Revolution end. 1905 revolution might've been a good time for the first wave of the purge. Keep in mind that a decade for a movement to form against an organisational entity on the scale of the Black Court purge is short paticularly in those days. French Revolution had a couple of decades behind it (I have another theory about the French Revolution. Well more Half WAG half Fan Fiction)
The next decade see's the remaining Black Court who without their elders turn to infighting and independent warlords and are slowly isolated and wiped out.
By 1923 their are only a few Black Court Vampires left. One of them possibly being or posing as Koschei the Deathless, and maybe two or three other nests Simon is keeping track of.
Simon then devotes himself and his apprentices to wiping out the remaining Black Court strongholds in Russia and possibly Eastern Europe effectively ending them as a world power.
Kemmler's Dark Hallow is an adaptation of an ancient spell suited to his Necromancy and twisted desire to suck souls out of people. I believe it was strongly based on the Black Court's spell. Adding in the key element of the Erlking.
