Geralt of Rivia is a witcher and the main protagonist of the Witcher series by Andrzej Sapkowski and its adaptations, including The Witcher (PC), The Witcher 2: Assassins of Kings, and The Witcher 3: Wild Hunt video games. Like all witchers, Geralt is a monster hunter for hire. He possesses superhuman abilities and is a master swordsman. During the Trial of the Grasses, Geralt exhibited unusual tolerance for the mutagens that grant witchers their abilities. Accordingly, Geralt was subjected to further experimental mutagens which rendered his hair white and may have given him greater speed, strength, and stamina than his fellow witchers.
Geralt is also known as Gwynbleidd, meaning "White Wolf" in Elder Speech. He was given this alias by the dryads, and is also called the Butcher of Blaviken after an unfortunate incident in that town.
Despite his title, Geralt does not hail from the city of Rivia. After being left with the witchers by his mother, Visenna, he grew up in their keep of Kaer Morhen in the realm of Kaedwen. In the interest of appearing more trustworthy to potential clients, young witchers were encouraged to make up surnames for themselves by master Vesemir. As his first choice, Geralt chose "Geralt Roger Eric du Haute-Bellegarde", but this choice was dismissed by Vesemir as silly and pretentious, so "Geralt" was all that remained of his chosen name. "Of Rivia" was a more practical alternative and Geralt even went so far as to adopt a Rivian accent to appear more authentic.
Later, Queen Meve of Lyria knighted him for his valour in the Battle for the Bridge on the Yaruga conferring on him the formal title "of Rivia", which amused him. He, therefore, became a true knight of Lyria, only to lose the title soon after for departing.