Timothy Snyder is a historian and professor at Yale University, specializing in Eastern and Central Europe, totalitarianism, and the Holocaust. His books have received widespread acclaim nationally and internationally from both academic and general audiences. His most recent book, "On Tyranny: Twenty Lessons from the Twentieth Century," explores the small, everyday ways a citizenry can resist the encroachment of government tyranny. He is also the author of "Black Earth: The Holocaust as History and Warning" and "The Road to Unfreedom: Russia, Europe, America."

Follow on Twitter: @TimothyDSnyder