Koun was born in Bursa, present day Turkey, as an Ottoman Empire citizen to a Greek mother and a Polish Jewish father. He was educated in Ottoman Turkey until the end of high school. He graduated from Robert College in Istanbul and then went to Sorbonne for his university education. As his family's economic situation worsened, he couldn't continue his education.
He had been praised all over Europe for his bawdy, colorful stagings of the 5th century BC political comedies of Aristophanes. In 1942, he founded the experimental Art Theater and its drama school.
Koun gave premieres in Athens of works by avant-garde European playwrights such as Bertolt Brecht and Luigi Pirandello. In 1962, Koun's production of The Birds by Aristophanes won first prize at an international festival at Paris.
He worked with famed actress Melina Mercouri. She played Blanche Dubois in A Streetcar Named Desire which was staged by Koun's Art Theater. Other playwrights that Koun introduced to Greek audiences include Jean Genet, Federico García Lorca and Eugène Ionesco.
He stayed politically active all his life which had a direct impact on his not having financial security in his life. His theater was responsible for training the golden generation of Greek movie actors.
Karolos Koun died on February 14, 1987, after suffering a heart attack, aged 79.
- Chambers, Colin. "The Continuum Companion to Twentieth Century Theatre". London; New York: Continuum, 2002, p. 329, ISBN 978-0-8264-4959-7.
- "Biography". Melinda Mercouri Foundation, accessed October 20, 2011.
- New York Times obituary