The Horus Heresy is an ongoing series of science fantasy books written by various authors. The series takes place during the Horus Heresy, a fictional galaxy-spanning civil war occurring 10,000 years prior to the far future setting of Games Workshop's Warhammer 40,000 tabletop miniatures wargame. The war is described as a major contributing factor to the game's dystopian environment. The books are published in by the Black Library, a Games Workshop division, with the first title released in April 2006; as of October 2016 the work consist of 40 , with more in the .