Ivan Bartley was an arrogant noble of a house in opposition to the Belmont Family & the uncle of Sona Bartley. He has strong ties with Dracula according to IDW's Castlevania: The Belmont Legacy comics.
First seen confronting Illyana Riktor in the market on the day of her wedding to Christopher Belmont, he openly comments on the 'Prince of Darkness' return, for which Illyana chastises him.
Later that night, while the revelers go to attend the wedding, Ivan & Sona lead a group of Cultists to the ruins of Castle Dracula to resurrect the Vampire.
Unfortunately, Dracula's strength fails to return, prompting Sona to usurp her uncle & offer her own blood to restore Dracula fully.
While he is never shown again following Sona's usurpation, it can be assumed that he either met his end at Dracula's hands or he was killed shortly after the vampire's death. Alternatively, as he is likely related to Elizabeth Bartley in some way, he may have escaped to inform her of what transpired.