Answer: I don't know of the book you read, but..
Authors use historical times and revise them in such a way it's believable, immersive, and informative. They make sure their use of history isn't changed into an outlandish fashion to fit the time it's set in. They usually do this because you can't go back in history and show them what happened, so you must create a fictional yet historical piece to preserve the time.
A show of understanding or non-understanding through facial expressions
Noun I believe would be the answer....
