It is the early 1600s, and Johannes Kepler's mother is accused of witchcraft. I love historical fiction. Apparently this was on CBC Canada Reads last year, but I only found out about it very recently.

Part of the historical background of this story is that "between 1625 and 1631, under the Catholic Prince-Bishopric of Würzburg, the Holy Roman Empire saw one of the biggest mass trials in European history, with an estimated 900 people executed in the Würzburg witch trials." (From wikipédia)