The Holy Grail War!
A battle for the omnipotent "Holy Grail," said to grant its holder's wishes!
After the Third Holy Grail War...
The Three Founding Families, who had originally created the entire Holy Grail System...
Einzbern, Tohsaka, and Makiri had been left weak and powerless.
This gave outsiders an opportunity, and in the end, the Greater Grail System was seized by "evil" forces! Later, other magi transported it elsewhere.
Thus, the Holy Grail War of Fuyuki City came to its so-called end.
However, once the Holy Grail War System of Fuyuki City's Three Founding Families was made public, the entire world was thrown into an uproar! From then on, across the world, Holy Grail Wars known as "subspecies" began constantly occurring in every territory inhabited by magi...
Summoning Heroic Spirits, something that had originally only succeeded under limited conditions, began to become commonplace. However, these subspecies Holy Grail Wars could summon only a limited number of Heroic Spirits, so they could not provide enough Mana for the Holy Grail, nor could they help magi reach the so-called Root.
The events began after Fuyuki City's Holy Grail was transported to Romania!
The local lords, the ancient Yggdmillennia Family, declared war on the Clock Tower, the magi's sacred ground in London, intending to establish an entirely new Mage's Association.
In order to emerge victorious in this battle against the Clock Tower, they used the Holy Grail System created by Fuyuki City's Three Founding Families and successfully summoned seven Servants!
To counter the Heroic Spirits summoned by the Yggdmillennia Family, the Clock Tower followed the principle that only Heroic Spirits could deal with Heroic Spirits. Using the Greater Grail's "emergency mechanism," they summoned another faction of seven Servants.
The Holy Grail itself also summoned a Servant of a special class—Ruler. The main