The Stolen Throne is a fantasy novel written by Harry Turtledove and set in the Videssos universe. It is the first book in the Time of Troubles tetralogy. The events depicted are strongly based on the historical interaction of Sassanid Persia and Byzantium in the 6th and 7th century. The first book depicts the rise of Sharbaraz (the analog to Khosrau II) to overcome the usurper Smerdis (Bahram Chobin) to become the King of Kings of Makuran (Persia) with the help of the Videssian Emperor Likinios (Maurice).
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The Stolen Throne Wikipedia(Text) CC BY-SA