In A Nutshell
Many people are under the impression that the modern vampire originated in Transylvania, but this is not quite accurate. One of the ancient vampire stories in Ireland is the Celtic legend of the undead Irish chieftain Abhartach. Given that Bram Stoker studied in Ireland for a long time, he was likely to be familiar with the tale. Even if it was not the sole inspiration, it was likely part of what became the vampire we know today.
The Whole Bushel
The legend says that back in the fifth century in the town of Slaughtaverty, Ireland, lived a brutal warlord known as Abhartach. In those days, the stories say, most lands were divided up into small areas ruled by petty kings, many of whom were hardly nice people. Abhartach was believed to have dark, magical powers and was greatly feared by his people, whom he was said to treat very badly. The townsfolk wanted to rid themselves of this troublesome king so they hired another local king to deal with the problem.
As far as coups go, it should have been simple enough. The king was murdered and buried standing straight up, which was considered the right and honorable way to do things considering his stature. However, unfortunately for the town of Slaughtaverty the horror was not over yet. Abhartach, in the legends, returned from the grave and demanded blood tribute from his people to sustain his energy. This led to Abhartach being slain and buried multiple times, each time rising again from the dead to seek blood from the living.
Eventually, the frustrated warlord tired of slaying this undead monster. He found some people learned in the ways of magic and asked them for a solution to his problem. They explained that the monster was essentially between worlds and could not be killed, but that he could be trapped under the earth if the proper steps were taken. These legends say he had to be killed with a sword made specifically of “yew wood,” which sounds reminiscent of the stake-through-the-heart theory often seen in popular culture. However, it does depart somewhat from modern lore in that to keep him in his burial site, he was also to be flipped upside down and covered with an enormous stone, as well as thorns.
There is much speculation that Bram Stoker heard of the legend while studying in Ireland and that it likely was much of the inspiration for his story. While it is hard to say for certain where all of Bram Stoker’s ideas originated from, the legend was fairly popular in Ireland at the time, so it seems like a safe bet that his Irish friends would have told him of the legend. Others point out that while Transylvania is usually given as the origin of the Dracula legend, Stoker himself had never even been to that part of the world. The only place in which he had lived around actual vampire legends was the Emerald Isle, where the original vampires came out of the primordial dark to feed upon the flesh of the living.