"Partner in Three Worlds" by Dorothy Duncan is an interesting choice for nonfiction winner. It is written in the 1st person from the perspective of Jan, a Czech who fights in the Canadian army to liberate his homeland in the Second World War. The bulk of the book describes Jan's life in then Czechoslovakia, where he is born, rises to prominence at a bank, and his subsequent fall due to an impetuous and ill-suited marriage. However, he manages to re-establish himself eventually as an artistic glass salesman, and eventually his move to North America. Duncan drew on an intimage knowledge of Jan through multiple conversations and one gets the impression that she is recounting Jan's stories verbatim as she often describes his thoughts and feelings (from a first person perspective).
One imagines that Jan must have been a great storyteller, as the book is very entertaining. It is difficult at times to remember that it's a work of non fiction rather than a novel. The book does do an excellent job of depicting Prague society in the early 20th century and additionally, the tensions that emerged in the lead up to the Second World War. There are also some excellent scenes near the end where Jan compares North Americans and Europeans.
Despite its unique narrative style (or perhaps beacause of it), the book works very well at both entertaining and informing.