al martino was a singer. he wanted to play johnny fontane. coppola removed him and replaced him with vic damone. martino went to his crime boss. the boss published papers about coppola switching the roles. eventually, damone gave up the part to please the mob. robert de niro originally wanted to play paulie gatto, but he quit. johnny martino took his place. the actors diane keaton, john cazale, and gianni russo got their roles in the film. coppola gave his family members roles. they included his sister talia shire, his daughter sofia and his father, carmine.