With this book, Kurts takes Deryni Rising, and transitions it from stand alone novel to introduction to a series, and she does a good job of it as well. There are many possible threads left over from the first book, and she picked them up adeptly.
Since there exists in Gwynned a race of Sorcerers known as the Deryni, there would exist people who hate and/or fear them. In this world they are found largely in the church. This sets up a conflict between the King and his Archbishop, the two single most powerful individuals in the kingdom. That all of this happens on the eve of war makes it more stressful for King Kelson, and Archbishop Loris would rather go down in flames than compromise.
The allegories that can be made for racism are abundant and clear, as the status of Deryni is inherited, so can one be held responsible for an accident of birth?