Goodreads asked Astra Crompton:

Where did you get the idea for your most recent book?

Astra Crompton This is the foundation for a long series of books set in the Ul-Zaorith universe. The Prophet's Tale trilogy is designed to give the ancient framework for why the world is the way it is, and to provide a history for all the tales that are to come. In researching the world, I learned about how it was shaped, and for this book in particular ancient Persian warfare was useful to learn more about technique.

flag