She has a complicated relationship with the girl Pansy, who is the secret love child of the manipulative Madame Merle and this character's indolent aesthete of a husband, Gilbert Osmond.  
As a child her French governess had eloped with a Russian nobleman while they were staying in Neufchatel.  Complications from her past arise in the person of the Interviewer reporter, Henrietta Stackpole but her fortune is created by the machinations of the sickly Ralph Touchette.  She has a complicated relationship with the girl Pansy, who is the secret love child of the manipulative Madame Merle and this character's indolent aesthete of a husband, Gilbert Osmond.  Finally confronted by the resolute American suitor, Caspar Goodwood, FTP, name this main character from Henry James' Portrait of a Lady.
As a child her French governess had eloped with a Russian nobleman while they were staying in Neufchatel.  
Isabel Archer (accept either name)