The notion as to which historical figure if any, was used by Bram Stoker as the original model for his fictional character Count Dracula, has never been adequately resolved for some fans. Some argue it was his boss at London's Lyceum Theatre whilst others show cause why it was a composite of the landlord class during Ireland's Potato Famine.
Sean Robert Curran however, the expert in Celtic history and folk-lore who lectured at the University of Ulster, stated Dracula was probably based on the fifth century Celtic Chieftain Abhartach from Derry, who drank tainted blood and subsequently died. According to Dr. Curran, Abhartach supposedly rose from his grave as an undead and demanded bowls of blood from his subjects. The word for tainted blood in Gaelic is 'droch'fhoula' pronounced 'droc'ola' (Agence France-Presse).
Since at a young age Bram's mother introduced him to Irish folk-lore and later he became a student of history, there's every chance he would have known about Abhartach.
Whoever the original model was, it is later explained in Bram's novel when, in the second entry in Mina Harker's journal of September 30, Van Helsing is quoted thus ". . . I shall then make it known to you something of the history of this man . . ." ". . . I have asked my friend Arminius of Buda-Pesth University, to make his record . . ."
The reply Van Helsing received from Arminius, as recorded in Mina Harker's journal, was: "He must indeed, have been that voivode (military ruler) Dracula . . ." ". . . for centuries after he was spoken of as the cleverest and the most cunning, as well as the bravest of the sons of the 'land beyond the forest' (Tran(s)-sylvania) . . ." "The Draculas' were," says Arminius, "a great and noble race."
Historically this fits the blood-thirsty Vlad III Tepes (one of the meanings of Tepes was Impaler), aka Vladislaus Dracula (or to be patronymically correct, Drăculeşti) whom in Eastern Europe was a knight whom following on from his father, was a member of the Sacred Order of the Dragon.
The word Drac in 15th century Romanian had two meanings; one was dragon and the other was devil. Some suggest that Stoker's Dracula refers to the Devil. They also assert that he was modelled off the Tepes Drăculeşti family, they can't have it both ways. This prominent dynasty fought under the Christian banner of a Sacred Order. No such order would have tolerated a name which meant devil. So the Tepes family surname of Drăculeşti, definitely meant dragon and never devil.