The defection of Russian intelligence officer Igor Gouzenko, stationed at the Soviet Embassy in Ottawa during and after the Second World War, is one of the highest-profile cases of defection in Canadian history—even said to be the event that triggered the Cold War.
Gouzenko exposed the extent of the Soviet spy network in the West at that time, including dictator Joseph Stalin’s efforts to steal nuclear secrets and the technique of infiltrating sleeper agents into target countries.