Casting Sharif in what is now considered one of the "most demanding supporting roles in Hollywood history" was both complex and risky as he was virtually unknown at the time outside Egypt. However, as historian Steven Charles Caton notes, Lean insisted on using ethnic actors when possible to make the film authentic. Sharif would later use his ambiguous ethnicity in other films: "I spoke French, Greek, Italian, Spanish and even Arabic", he said. As Sharif noted, his accent enabled him to "play the role of a foreigner without anyone knowing exactly where I came from", which he stated proved highly successful throughout his career.