Cavael studied typography and applied graphics at the Städelschule in Frankfurt from 1924 to 1926. His talent was soon discovered as he received a scholarship during his studies. He became a teacher for graphics at the Handelsschule in Frankfurt and attempted first experiments with abstract painting. During a trip to the Bauhaus in Dessau in 1930 he met Kandinsky, with whom he developed an amicable contact, which also remained after Kandinsky's emigration to Paris. The same year he was released from his teaching position due to Chancellor Brüning's emergency decrees, which resulted in economy measures. He moved to Berlin, where he worked as a freelance artist. In 1933 he had his first important exhibition in Schloß Braunschweig together with Josef Albers, which, however, was closed down by the Nazis on the very day of its opening. Both painters were banned from exhibitions. Cavael moved to Garmisch and continued secretly to paint. After being denounced in 1936 he was taken to the Dachau concentration camp for four months. Then he was not only banned from exhibiting but also from painting, as he was dismissed from the Reichskulturkammer. After the war he resumed his artistic work, which was only happening in secret during the years of ban. In 1949 Cavael and Baumeister, Winter, Geiger among others established ZEN 49, at that time the most important group of artists in Southern Bavaria working Non-representational. From 1954 onwards he lived in Munich. In 1955 he was given a guest professorship at the academy of arts in Hamburg and taught at the Volkshochschule in Munich between 1956 and 1973. During this time he received several honours, e.g. the art prize of the city of Munich in 1957. He was invited to the Biennale/Venice in 1958 and received the first prize at the Graphiktriennale in Grenchen/Swittzerland. The Kunsthalle Baden-Baden, the Kestnergesellschaft Hanover and the Lenbachhaus Munich (1968 and 1978), amongst others, arranged individual exhibitions of his works. In 1978, Cavael is awarded the Lovis-Corinth-Preis. He died in Munich in November the following year. Cavael was one of the most important representatives of Non-representational painting in Germany.