Sometimes historical fiction seems more like narrative nonfiction than fiction because the book just breathes accuracy. An example of a fiction book that reads like nonfiction is Schindler's List by Thomas Keneally. Oscar Schindler was a real person who really did make a list of Jewish workers that he "needed" for his jobs. His efforts saved 1300+ people from sure death. So why is the book fiction? Because the book includes conversations and dialogue between characters that no one can prove actually happened. The bones of the story are correct but the interesting little details are fictional.
Other times historical fiction books are clearly fictional, sometimes including magical or fantastical elements, but if the author has done the needed research the reader can still benefit by learning new information. Or the book may lead the reader to do their own research about the topic.
Recently I have read two historical fiction books and though I liked one of the books better than the other, I actually learned more from the book I liked the least. Let me tell you a little about each.
The Lost History of Stars by Dave Boling is about a family caught up in the second Boer War in South Africa, around 1900. The Boers were fighting the British military over gold and diamond rights. The Boers, descendants of Dutch sailors, refused to roll over in the face of a much mightier army. They used guerrilla-type tactics of hit and run and ambushing. The British became so frustrated that they started taking the families of the combatants into custody and imprisoned them in concentration camps. Over 22,000 women and children died during this imprisonment, often from diseases like measles which they had no or little immunity to. The world all gasped at the horrors of the holocaust during the Second World War but few knew the British did a similar thing a few decades before that time. The family in this fictional work was deeply and profoundly affected by this war.
There were the a few weaknesses of The Lost History of Stars, however. When a book is set in an exotic or different setting the writing should be so descriptive that the reader can practically see or imagine what that setting looks and feels like. In one scene lions are roaring in the background. Another describes an incident with a snake. Otherwise there were few descriptions that allowed me to travel to South Africa in my mind. Another thing that seemed missing was authentic language. Boers (Afrikaners) speak a Dutch-hybrid language called Afrikaans yet few of these words were used to make the story seem accurate. Lastly, the story line was a very tragic one about the horrible things that happened to people in the concentration camps, yet I did not feel the outrage or anger that I should have when confronted with the details. And I wasn't alone with this thought. Everyone in my book club felt the same way. The writing didn't evoke strong feelings of empathy.

Unlike the previous book, Caleb's Crossing did use language which seemed like the language of the 1660s, very stilted and full of religious aphorisms. The descriptions of the island, the Indian villages, the local farms, and the town of Cambridge gave a full and complete picture of the setting. Though I liked this book better than The Lost History of Stars, it did not cause me to do any additional research on my own. Each of the books had their own strengths and weaknesses.
For my taste, I like historical fiction to also be educational. I like a story line which carries to plot along but I also want authentic details which will pique my interest and knowledge-base. Sometimes the least likely books can do the best job of that. One book that comes to mind is Revolution by Jennifer Donnelly. In this book, set in modern times, the main character Andi goes to Paris. She finds a journal of a girl who lived two centuries before. As she reads it she actually time travels to that time period and learns about the French Revolution up close and personal. Even though the book uses magical realism, I learned more about the French Revolution than I ever had from textbooks and I enjoyed the experience of reading it very much.

Good historical fiction should help catapult the reader back in time to certain place or event and help the reader understand just a bit what it was like to live during that time. Great historical fiction will go one more step and cause the reader to do their own research to learn more just because they want to know more.
What are some of your favorite historical fiction books?