Ingarden became a professor at Nicolaus Copernicus University in Toruń in 1945 shortly after the war but was banned in 1946 because of the Communist government. He then moved to the Jagiellonian University in Kraków, where he was offered a position. In 1949, however, he was banned from teaching due to his alleged idealism, supposedly being an "enemy of materialism". In 1957 he was reappointed at the Jagiellonian University after the ban was lifted, and so he went on to teach, write and publish.