Anastaz di Zagreb was born as the son of a wealthy textile importer and had an early interest in the supernatural. His father, however, disapproved of this and sent him to Oxford, where he should receive a solid education. At first, he obeyed, turning into a staid young man, until he met a stage magician in a local pub. Fascinated by the man's illusory talents, he decided to learn the techniques of stage magic. He practiced throughout his studies and even after he graduated at Oxford and went to the London School of Economics, while also joining a secret society called the Magic Ring. During one night, he encountered a Tremere who fed on a women in the backyard. He managed to scare the vampire off, but when he turned to his colleagues, they just scoffed at him. Back at home, the Tremere awaited him, revealing himself and explaining to di Zagreb the power of Thaumaturgy. Eager to learn more about this real magic, the young man cast his old life aside and joined the ranks of Clan Tremere. He spent 25 years in Vienna, studying Thaumaturgy and rising quite fast through the ranks of the Clan.
The previous Justicar of the Clan made di Zagreb his Archon. During this time, he faced various other supernaturals and became a prodigy on matters of the occult, but his friendly demeanor and altruistic behavior never let him advance in inter-Clan politics. When the new Justicar was chosen in 1998, Regent Jean St. Frederique put him forth as a candidate, hoping to control the still young vampire as a mentor and adviser. While still young and inexperienced by comparison with his peers Brujah Justicar Jaroslav Pascek. Currently, Anastaz di Zagreb has ambitious plans to conquer Montréal for the Camarilla.