Lissitzky's Proun period works are undoubtedly his most important. Having spent his formative years as an illustrator of Jewish children's books, in 1919 Lissitzky was invited to join the Vitebsk art school by Marc Chagall. The scool was dedicated to the non-objective art of the new Russia as personified by its chief theorist Kasimir Malevich. Trained as an architect, Lissitzky added a new dimension to the flat planes of Malevich's suprematism in a series of architectonic oils and watercolours he christened his Prouns.
The debt owed to 20th century non-objectove art to Malevich's suprematitst experiments has been much discussed but it would be a mistake to overlook Lissitzky's legacy: he greatly influenced Malevich's own arhcitectural experiments of the mid 1920s, Russian architects of the 1930s would hardly ever dared be so inventive had he not prepared the way and the De Stijl movement confirmed its allegiance to Lissitzky when it published a Dutch edition of his Story of two Squares in the regular edition of De Stijl magazine in the autumn of 1922.