Because of certain minor details such as whether Gilgamesh had seen Excalibur or not during the 4th Holy Grail War, Fate/Zero is treated as being in an extremely similar parallel world to Fate/stay night. Fate/Zero takes place 10 years prior to the events of Fate/stay night in the year 1994, detailing the events of the Fourth Holy Grail War in Fuyuki City. Originally founded by the Einzbern, Tohsaka, and Matou families, the war involves seven Masters and seven Servants under seven classes: Saber, Lancer, Archer, Rider, Caster, Assassin and Berserker.