Vampires originally come from Ur near Sumeria and before the fall of Chaldea. Vampires ruled Ur until our arrogance and the Juns overthrew us and we scatterd. Many wound up in Egypt and in Greece. To read more about Ur see my Ur, Chaldea and Mesopotamia page.
I have an ancient Egyptian Vampire Myth on my ancient myths page.
When we arrived in Egypt our affinity for cats, our cat-like appearance and actions, our light sensitivity and strong mental abilites (majick/magick) made the Egyptians believe we where the hi-priests and priestesses of the gods.
Yet again our arrogance was our down fall. When Amhenhotep IV was killed by his uncle in 1379 BC, his son Tuthankaton turned away from the worship of the one god, Ra, and all of the "priests" fled to prevent their deaths. Many of these wound up in Ireland (which is where you get the kilt from according to some beliefs) and Russia.
When we fled, humans had begun to migrate(like the gypsies) and formed trade routes which not only spread art and culture and myths of our kind but it also spread disease to people who had no immunity to such diseases and created plagues. Blood became tainted with things similar to AIDS.
When the blood supply became tainted we had one of three choices (same as Irish had during potato famine). 1 migrate, 2 die of starvation, 3 find a new food source.
This is why there are some vampires who still drink blood and some who feed on energy directly, without going through the blood to get it.
This is happening again with the outbreak of aids/HIV and other such diseases so many sanguinarians are beginning to become either both types of vampire or totally turning over to psi-vampire and/or are getting in a relationship with a psi-vampire.
They can feed on each other with no harm done for extended periods.
Psi-Vampires are not higher evolved than sanguinarians, we just adapted to our environment differently than they did. Where sanguinarians moved to find safer blood we moved away from blood and straight to pranic energy.
Those that did not move to places that allowed anyone to enter freely found other ways to enter countries with-out question. They joined the aryans, mongols, the golden horde, the moors, the crusades, the gypsies, wandering minstrels and teachers of foreign cultures to the young members of various royal families.
There is at least one war every generation(20 years) and there is always a skirmish somewhere in the world. All vampires had to do was join the front lines. Who would notice an extra body here or there and besides most of us helped those that were dying in great pain on the fields to pass quickly and with as little pain as possible onto the other side. The British actually made a treaty with the Irish to keep the Irish women (we are 75% female by the way) off of the battle fields because where the men left their wounded enemies on the fields the women were known to kill the dying and seriously wounded (I guess we weren't discrete enough).
The world has become so small due to technology that it has become harder for us to go from place to place, to disappear or start over without someone asking for references or our history. We can no longer just disappear under some rock to hide. Therefore it would be very, very stupid of any vampire to kill or attract attention to our kind.
Our greatest strength and defense is that no one believes we are real. We intend to keep it that way!