Hermiod was an historian in the early Second Age who famously chronicled the many deeds of the early Slayer Dragons roughly 1000 years before his time, at the begining of the Golden Age. His book, Tracts of the Dragon for to Slay, was considered the seminal work for many years and became a mainstay in the university market.
Famously, because roughly 500 years after his death, it was discovered that the majority of Hermiod's work was an outright fabrication. He avoided the better-known Slayer Dragons of the time and made up extensive stories about the less popular ones, often using only the correct name or inventing completely new Slayer Dragons on his own. Unfortunately, by the time his forgeries were discovered, much of his work had permeated the standard history texts of the time, making it nearly impossible to separate fact from fiction. This was made all the more evident when it was discovered that some of Hermiod's forgeries were still widely believed in the Fourth Age, when the Accepted Histories were composed.