On September 5, 1945, cipher clerk Igor Gouzenko walked out of the Soviet Embassy in Ottawa with 109 classified Soviet documents in his suitcase. Gouzenko had made the choice to defect - and his decision arguably sparked the beginning of the Cold War.

Guest host Nick Johnston joins us to explore the Gouzenko Affair and its broad impact not just on Gouzenko and his family, but on the larger postwar era.

Notice History is the official podcast of Know History, a historical research company based in Ottawa. Visit our website at knowhistory.ca/podcast, or follow us on Twitter and Instagram @NoticeHistory.