Warhol was as soaked in images as anybody. Through the 1950s he was a successful commercial artist, known for adveritsements showing distinctive blotty ink drawings of shoes. But he was also a devoted gallery-goer, determined to break into the citadel of high art. Although he is often talked about as the og-father of pop art, he was beaten to the citadel by several other aspirants, notably Roy Lichtenstein, whose giant blow-ups of comic-book images began in 1961. Desperate, Warhol turned to Muriel Latow, an adventurous gallery owner. According to Tony Scherman and David Dalton in their book "Pop: The Genius of Andy Warhol," he said to her, "Just tell me what to paint."
In return for a $50 cheque, she told him "Think of the most common, everyday, instantly recognisable thing." He thought of his doting mother, Julia Warhola.... Julia lived in the basement of the Manhattan town house he had bought with money from his advertising commissions. She used to give him soup for lunch—Campbell's Soup.From the article A One-Man Market by Bryan Appleyard
in The Economist's insert, Intelligent Life