Alucard as most already know has a rather ironic name. It is "Dracula" backwards. This is a nod to the novel by Bram Stoker which is titled "Dracula". Alucard himself is a homage to the infamous antagonist as in Hellsing he actually 'is' Dracula. Also, Alucard is shown to have been killed by Professor Abraham van Helsing via a stake to the heart, the most obvious nod to the novel. Most of the events in Hellsing itself also parallel those in the book.