Marc Chagall is considered one of the most significant Russian-Jewish painters of the 20th century. On account of his beautifully coloured and poetic works, he is often classified as an Expressionist. In his works, he developed unique, timeless-poetic pictorial worlds which draw upon the rich Russian folk art, Jewish mysticism as well as oneiric images. His recurring motifs include the lovers, the crescent, the cock and the Jewish shtetl. Up until old age, Chagall also created extensive etching cycles and lithographs, and he accepted numerous public commissions for church or synagogue glass windows as well as ceiling and wall frescoes.