While I didn’t start writing the second section of the book until I was in my second year of university, I actually created the character of the immortal Empress of Toxai back in high school during a creative writing exercise. As with any character, the initial spark of creation is not what the flame becomes; and Annabelle is no different as she was originally fully grown and much more tyrannical than how she appears in the book. But one thing that never changed was how the Buddhist interpretation of reincarnation, and specifically that of the Dali Lama, influenced how Annabelle achieved immortality.
Though I’m sure I’m wrong about this in reality, as I learned the broadest of strokes about Buddhism, learning that the spirit of the Dali Lama seemed to take over that of the child who will become the next Dali Lama was an interesting concept to me. Though I’ve since learned that the child is born with this spirit within them and it slowly emerges over time (similar to the show Avatar: The Last Airbender and Legend of Korra), the thought of this possession-esque really intrigued me as a way a world leader would work. As I do with everything that influences me, I bastardized this into what we see in the book in a much more Supernatural possession rather than true reincarnation.
But that isn’t where the influences stopped. There’s also the way in which those who rule in Annabelle’s place as she finds her new body determine the child coming to the palace is indeed the real Annabelle. Buddhist monks show a variety of objects to the potential Dali Lama, and depending on what they choose is a how they determine the real reincarnation from those who are not. Annabelle, and by extension Toxai, takes a less likely to be influenced by chance approach to proving her identity. Before she dies, Annabelle would take her three most trusted advisers and servants and tell them secrets about herself that no other people would know about her. Talking to each individually, Annabelle would tell them each different things and they would then devise questions that one of the others would ask and report her answers back to the question inventor. She would also hide her most prized possession, the Eternal As We Are ring, during one of these private conversations and only retrieve it when being questioned by the person she was talking to when she hid it. Correct answers to the questions, along with knowing the location to the ring, are what help determine that she is indeed the returned Empress.