Igor Sergeievitch Gouzenko, Soviet intelligence officer, author (born 26 January 1919 in Rogachev, Russia; died 25 June 1982 in Mississauga, ON). Gouzenko was a Soviet cipher clerk stationed at the Soviet Union’s Ottawa embassy during the Second World War. Just weeks after the end of the war, Gouzenko left the Soviet embassy with documents that proved his country had been spying on its wartime allies Canada, Britain and the United States, prompting what is known as the Gouzenko Affair. Gouzenko sought asylum for himself and his family in Canada. His defection caused a potentially dangerous international crisis that many historians consider the beginning of the Cold War.