Haha... origins of vampires...
In White Wolf's World of Darkness, vampires descended from Caine,
who slain his brother Abel. He was made to drink blood and only
blood by God for his crime (the first homicide). Caine was taught
the art of vampirism by the First Woman, Lilith. Caine is Cain in
the Bible; Lilith is entirely fictional.
As for Dracula, he was originally a prince of Romania
(Wallachia[spelling?], to be exact), who somehow turned into a
vampire after his death. He was already rather bloodthirsty (pardon
the pun) and cruel in his method of dealing with people who were
against him (impaling them on wooden stakes)...
Oh, if you watch this Hong Kong drama series (My Date with a
Vampire II and III only; vampires in the first part does not seem
to share the same origin), the vampires are descended from a
powerful vampire called Jiang Chen, or vampire commander (as he is
subtitled, although the 'Jiang' is tone 4, for 'general' and not
tone 1 for 'vampire'...)
This Jiang Chen, in turn, belongs to a group of people called Pan
Gu. Yes, that is the same Pan Gu in Chinese Mythology who created
the world, only that in the drama series, Pan Gu is not a single
entity but a group/tribe of people.
There are also two other members from this Pan Gu tribe which
appeared in Part III, both of whom are considered deities, and one
of whom is even the image upon which Man was created (by the
goddess Nuwa).