Konstantin Shteppa

Konstantin Feodosyevich Shteppa was a Soviet and American historian of German-Ukrainian descent. He studied history of the Byzantine Empire, the Orthodox Church, late medieval history of Ukraine and the history of Stalin's purges. Originally an NKVD informant, he switched allegiance to the SD, the intelligence agency of the SS and the Gestapo, during World War II. He immigrated to the US after the war, where he taught and worked for Radio Free Europe/Radio Liberty.