During his lifetime, he was an Akoimetai monk sent to Alexandria to copy some of the texts stored there. A firm believer in the Tzimisce ideal of enlightenment, he found a tome that told him about ether and the possibilities it granted to those who would control it. When he stumbled through the night, his copy of the tome tightly grasped, he was Embraced by a pack of young Ravnos, and he accompanied them until the point when they reached Constantinople.
He settled there, despite the rejection of his former Tzimisce masters, under the protection of Caius, who wanted to use the artificial devices Gregory made to impress Michael. During his time in Constantinople, he further improved his etherical workings and even took an apprentice, a young girl named Zoë. He also became a friend to Petronius and was initiated into the Dream Circle.
During the burning of Constantinople, he nearly killed Zoë in Frenzy and, in desperation, Embraced her to save her life. Horrified, he tried to shut Zoë away from the world of the undead and even from her own nature, leaving his ignorant childe to be educated by their Cainite traveling companions as they fled Constantinople. In Lombardy, the pair were abducted by Templar witch-hunters, and Gregory was slain. Zoë survived thanks to the intervention of their ally Andreas Aegyptus, and went on to hunt her sire's murderer across Europe.