Henryk Stażewski (pronounced: STa-zhef-skee; 9 January 1894 – 10 June 1988) was a Polish painter, visual artist and writer. His career spanned seven decades and he is considered a pivotal figure in the history of constructivism and geometric abstraction in Poland. Stażewski was one of the few prominent Polish avant-garde artists of the interwar period who remained active and gained further international recognition in the second half of the 20th century.Stażewski rose to prominence as a co-founder of Blok, Praesens, and a.r. group, three interwar artist collectives which spearheaded the development of Polish Constructivist art. During the 1920s and 1930s, he became acquainted with and influenced by prominent European avant-garde artists, including the Soviet Suprematist painters Kazimir Malevich and El Lissitzky, the Dutch de Stijl artists Theo van Doesburg and Piet Mondrian, as well as the French Cubist painter and later founder of the Abstraction-Création collective Albert Gleizes, among others. Stażewski's career was hindered by the outbreak of World War II and most of his work was destroyed during the Nazi occupation of Poland. After the end of the war in 1945, he returned to painting but faced the cultural constraints resulting from the imposition of Stalinism and Socialist Realism in Poland.
Following the cultural and political Thaw of 1956, Stażewski began working on abstract relief sculptures, a medium that preoccupied him in the following decades and became his most recognized body of work. First exhibited in 1959, Stażewski's reliefs deployed diverse media and embraced various non-figurative visual vocabularies inspired by his interwar investigations into geometric abstraction. During the 1960s, still working behind the Iron Curtain, Stażewski helped facilitate unofficial cultural exchanges with numerous Western artists. In 1966, he initiated a years-long collaboration with the non-commercial gallery space Galeria Foksal in Warsaw, which played a critical role in the development of the Polish post-war avant-garde. Working alongside Christian Boltanski, Tadeusz Kantor, Allan Kaprow, Edward Krasiński, Annette Messager and other contemporary artists who exhibited at Foksal, Stażewski gained a reputation as a leading Polish abstractionist of the 1970s and 1980s.
Stażewski's works are included in permanent collections of museums in Europe and the United States. For his contributions to Central and Eastern European culture, the artist was awarded the 1972 Herder Prize.