Subgenres
In the 20th century, historical novels started branching into different sub-genres.
Arthur Conan Doyle greatly influenced historical mysteries with his Sherlock Holmes series and several authors followed like Iain Pears, Paul C. Doherty and David Liss.
Romantic themes have also found their way in historical narrative i.e. historical romances, by mostly female authors, starting from the Gone with the Wind by Margaret Mitchell and others in the 20th century, like Eleanor Hibbert and Philippa Gregory.
Another popular trend is the nautical historical novels, which started with the pirate novels about Sandokan by Emilio Salgari and was further developed by novelist like C.S. Forester's Hornblower series and Patrick O'Brian's Aubrey-Maturin series, set in the back-drop of the Napoleonic Wars.
The science fiction genre also contains a couple of historical sub-genres; alternate history such as Robert Silverberg's Roma Eterna, and time travel with historical settings, such as the "Company" stories of Kage Baker.
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