The Stasi has been described as one of the most effective and oppressive secret police organizations ever conceived. Modeled on the Soviet Union's NKVD, a forerunner of the KGB, the Stasi served as the state security service of East Germany from 1950 to 1990. Few were privy to the Stasi's methods of surveillance and espionage until the fall of communism, when hundreds of thousands of recovered files and documents revealed the full extent of the terror and intimidation maintained on East German citizens.
You can learn more about the terrifying history of the Stasi and the individuals responsible for running it by clicking through this gallery.