Gilgamesh, Class Name Archer, is the Archer-class Servant of Tokiomi Tohsaka in the Fourth Holy Grail War of Fate/Zero. He later forms a new contract with Kirei Kotomine that lasts ten years later into the time of the Fifth Holy Grail War of Fate/stay night. He is one of the Servants summoned by Ritsuka Fujimaru of the Grand Order conflicts of Fate/Grand Order.

The great half-god, half-human king of heros born from the union between the King of Uruk, Lugalbanda, and goddess Rimat-Ninsun. He ruled the Sumerian city-state of Uruk, the capital city of ancient Mesopotamia in the B.C. era. He was an ultimate, transcendent being so divine as to be two-thirds god and one-third human, and no others in the world could match him. He was a despot possessing high divinity who believed he was invincible. He is not merely a legend, and is said to have actually existed and ruled during the Sumer Dynasty five thousand years ago. He was the King of Heroes who possessed all things in the world, whose tale is recorded in mankind’s oldest epic poem, the Epic of Gilgamesh which portrays Gilgamesh as a hero, destined to be king and achieve great feats, who is driven to meet his destiny, facing challenges together with his best friend Enkidu.