Gellert
Gellert is a character from J.K. Rowling's Harry Potter series. He is primarily known as the Dark wizard who was a close friend and former lover of Albus Dumbledore. Gellert Grindelwald rose to prominence in the early 20th century, seeking to unite the wizarding world and dominate over Muggles. His ideology was based on the belief that wizards were superior and should rule non-magical people, a philosophy he expounded upon in his pamphlet "The New Era of Wizardry."
Grindelwald's early life and education are not extensively detailed, but it is known that he attended Durmstrang
His reign of terror was eventually brought to an end by Albus Dumbledore in a legendary duel