The first modern vampire was born at the same time as another great horror cliché: Frankenstein. While in Geneva, Switzerland, Lord Byron, Percy and Mary Shelley, and Byron’s doctor Polidori decided to write some ghost stories—yeah, they were doing it on a whim, while on vacation—and Mary Shelley indubitably won by writing the first science fiction novel ever. Polidori wrote The Vampyre—and he based it on Lord Byron himself.
Lord Byron was probably one of the world’s first literary bestsellers. He was famous for plenty of things: popularizing the bad boy persona, shaping modern tourism, but especially his sexual proclivities. So when the original vampire story was being written, the vampire took on Byron’s boisterous aristocratic mien—but also a lot of the “my love is fatal to my lover” mythology of Byron’s sexuality.