1910s - Moscow (Russia) - Film Director Lev Kuleshov demonstrates the Kuleshov effect: "a mental phenomenon by which viewers derive more meaning from the interaction of two sequential shots than from a single shot in isolation".
1920 - Paris (France) - Jacques Copeau introduces mask improvisation at the Ecole du Vieux-Colombier.Berthold Brecht introduces the notion of Distancing Effect (Verfremdungseffekt) in an essay first published in a London revue.
1944 - Northampton (US) - Experimental psychologists Fritz Heider and Marianne Simmel use a simple video animation to study the way audiences compose narratives.
1951 - Milan (Italy) - Jacques Lecoq creates the Theatre School of the Piccolo Teatro.
1959 - Opole (Poland) - Jerzy Grotowski founds the Laboratory Theatre.
1963 - (US) - Viola Spolin's Improvisation for the Theater is published.
1975 - New York State (US) - Jonathan Fox develops Playback Theatre.
1977 - Quebec (Canada) - Robert Gravel's Ligue Nationale d'Improvisation stages the first public performance mixing improvisation with sport.
1978 - Calgary (Canada) - Keith Johnstone's TheatreSports first public match.
1978 - Ottawa (Canada) - Carleton High School's Improv Olympics is founded.
1979 - (Canada) - Impro: Improvisation and the Theatre by Keith Johnstone is published.
Main source (with several additions): The Novelty of Improvisation: Towards a Genre of Embodied Spontaneity (open access) by David Alfred Charles - PhD Dissertation - Department of Theatre - Louisiana State University, August 2003. All rights reserved.