William Sharp was born Leon Schleifer in Lemberg, Austria. He attended the Academy for Arts and Industry there and continued his studies in Kraków, Poland, Berlin, and Munich. After service in World War I, he became a newspaper artist in Berlin and a well-known etcher. His biting political cartoons provoked threats of imprisonment from the National Socialists, so he left Austria for the United States in 1934, where he changed his name and found work as a courtroom artist and a staff artist at Esquire magazine. Sharp contributed illustrations to numerous periodicals including The New York Times Magazine, Life, and Colliers. He illustrated books for several publishers and produced several compilations of his illustrations.