In season 5 Eric states that he has loved Nora for almost 600 years, but in this episode it is shown that Nora was still human in 1665, meaning that she can not be more than 380 years old.
Jeanine Anderson, the bank employee in this episode, also played a customer at Merlottes in season 1 episode 4 "Escape from Dragon House". Whether or not it's the same character is unsure.
The plague depicted in this episode is the Great Plague of London, which was the last major epidemic of the bubonic plague to occur in England.