Stefan Knapp (1921 – October 12, 1996) 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.
Knapp was born in Biłgoraj. His father's name was Antoni and his mother was Julia, née Wnuk.
In 1935 he began studies at the Lwów Polytechnic. After the outbreak of World War II the Soviet Union occupied Lwów, murdered Knapp's father and sent Stefan to a gulag in Siberia. There, among other things, he worked building schools for Russian children who had been orphaned because their parents had been imprisoned or murdered for political reasons. While in the Gulag, because artistic endeavors were limited, he made chess sets out of bread and playing cards out of trash for his fellow prisoners.
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. Knapp began his training as a pilot on 29 June 1942 in Hucknall. He served as an officer and Spitfire pilot in the Royal Air Force. While in the RAF Knapp pursued his art by painting or sketching portraits of his fellow pilots in 318 Squadron. After 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 the Slade School of Fine Art.