What is the author's perspective in the nonfiction book, The Zookeeper’s Wife?

The Zookeeper’s Wife is written in third person from the perspective of Antonina. It is written in past tense. The book is a non-fiction work and adheres to the genre in that it recounts true historical facts backed up by research, but it also contains elements of a fiction book in that the author engages in sections of vivid description and utilizes conventions like metaphors that are more often seen in a work of fiction.