After German occupation of Czechoslovakia in 1939, Peroutka was forced to write propaganda for the Nazis. He didn't listen and in April 1939 issue of "Přítomnost" he wrote an article "Dynamický život" (Dynamic life) about the 50th birthday of Adolf Hitler. In this article he acknowledged Hitler's power, but refused that Czechs should listen to him. For this he was sent to concentration camp, but was released after few days. Although, a few months later in September 1939 he was jailed again, along with other potential enemies of Nazi regime.