René Klapač was born in Paris into a Czech family that moved to the USA shortly afterwards. He studied at the Graphic School in Cleveland, Ohio and at the International Correspondence Schools of Scranton, Pennsylvania. In the early 1920s he returned to Czechoslovakia, graduated from the Academy of Applied Arts in Prague afterwards and published his first short comics in the satirical magazine Kopřivy (Nettles).
He spent the beginning of the 1930s in Paris but he came back to Prague in 1933. It was there that he started a successful career as a comic artist. He cooperated with children's magazines such as Malý čtenář (Little Reader) and Malý zpravodaj (Little Bulletin), and created many funny animal comics visibly influenced by Disney's production. However it’s interesting that his series 'Kačák detektiv' ('Detective the Duck') began a year before the official film debut of Donald Duck.
Klapac's comics were very progressive in the Czech context because they used speech balloons and not the verses below each panel. But his most successful project 'Punťa' ('Spotty') was forced by the domestic conventions to the more conservative form without balloons. These stories of a small human-like dog and his friends were first printed in the magazine List paní a dívek (Weekly for Ladies and Girls), but by 1935 Punťa got its own comic magazine.
The monthly (and later semi-monthly) periodical was the first commercially successful journal focused on comics and it published also translated material and pictorial stories by other Czech artists such as Emil Posledník or Hermína Týrlová. However the magazine was banned by Nazis in 1942. During World War II, René Klapač drew the humorous series 'Optík a Pesík' ('Optimist and Pesimist') for the newspaper Polední list (Noon Gazette) but he never did any story with a political undertone.
After the Communist putsch, he immigrated to the USA. He worked as an illustrator and maybe as a comic creator but no works are known.