This is a historical romance novel written by an anonymous author who published a series of books about Elizabethan era England.

Excerpt:

"I denounce thee, in the presence of this menial, as a traitor and a spy!" A flash of anger mounted to Hildebrand's cheeks at these words, and his rapier, on which his grasp had already been fastened, leaped from its scabbard on the instant. "Such terms would provoke an angel! Stand on thy guard!" he said and jumped."