Igor Gouzenko

Igor Sergeyevich Gouzenko (Russian: Игорь Сергеевич Гузенко [ˈiɡərʲ sʲɪrˈɡʲejɪvʲɪtɕ ɡʊˈzʲɛnkə]; Ukrainian: Ігор Сергійович Гузенко [ˈiɦor sɛrˈɦijovɪtʃ ɦuˈzɛnko]; January 13, 1919 – June 28, 1982) was a cipher clerk for the Soviet Embassy to Canada in Ottawa, Ontario. He defected on September 5, 1945 – just three days after the end of World War II – with 109 documents on Soviet espionage activities in the West. This forced Prime Minister Mackenzie King to call a Royal Commission to investigate espionage in Canada.

Gouzenko exposed Joseph Stalin's efforts to steal nuclear secrets, and the technique of planting sleeper agents. The "Gouzenko Affair" is often credited as a triggering event of the Cold War, with historian Jack Granatstein stating "Gouzenko was the beginning of the Cold War for public opinion" and journalist Robert Fulford writing "I am absolutely certain the Cold War began in Ottawa".The New York Times described Gouzenko's actions as having "awakened the people of North America to the magnitude and the danger of Soviet espionage."

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