In the past, the "Holy Grail War" was held in a city called Fuyuki, where seven magicians and heroic spirits participated. However, during the chaos of World War II, "a certain magician" forcibly took away the Holy Grail. Decades later, the Chikaiju clan held high the Holy Grail as a symbol, rebelled against the Magic Association, and declared independence. The angry Magic Association sent assassins, but they were counterattacked by the summoned Servants.