Stefan Knapp was a Polish born painter and sculptor, who worked in Great Britain. He developed and patented a technique of painting with enamel paint on steel facilitating decorating public architectural structures.

After the outbreak of World War II, Soviet Union occupied Lwow, murdered Knapp's father and sent Stefan to a gulag in Siberia. He was released in 1942 after the Sikorski-Mayski Agreement was signed between Poland and Soviet Union. He joined the Anders Army and volunteered for the air force, hence he was shipped to Great Britain. He served as an officer and Spitfire pilot in the Royal Air Force.

At the end of the war, he remained in London and took advantage of a veteran's stipend to further his studies at the Royal Academy and at Slade School of Fine Art. Knapp was known for producing murals of unprecedented size with materials which were meant to last for thousands of years.

He received wide attention and acclaim during his exhibition in London in 1954. He was one of the best known Polish artists working in Great Britain. He wrote an autobiography "Kwadratowe Slonce" (The Square Sun) about his life in the Siberian gulag. He died in 1996 at his studio in London still working on his art.