Vampires
the word vampire likely comes from the word vampyre
vampyre comes from the word vanpyre
Van meaning blowing
and pyre meaning a religious funeral service

This shows us that vampires are likely pagans
pagans have historically required (some tribes but not all) that their members (of the tribe) had Near Death experiences

as those with near death experiences could better comprehend death

These Vampyres (pagans) likely lived in cold regions
and were likely exiled by the christian converters
and probably only had access to dead corpses (likely killed as devil worshipers) and resorted to canibalism (of the dead) to survive

they were likely killeed by fire (burning of the stake)
hence called Van (blow) Pyres (Death (funeral) by fire)

THERE ARE LIKELY NONE OF THESE VAMPIRES STILL ALIVE

sources

http://www.merriam-webster.com/dictionary/van

http://www.merriam-webster.com/dictionary/Pyre