The Czar's Madman by Jaan Kross
This historical novel is about a Livonian nobleman, Timotheus von Bock, who has married a peasant girl named Eeva to prove everyone that good men are equal before nature, God and ideals. Eeva's brother Jakob analyses von Bock's life throughout his journal and tries to figure out if the nobleman is truly mad as everyone seems to believe. The Czar's Madman is arguably one of the best-known Estonian novels in the world.