The Godfather is a 1972 American movie widely responsible for inspiring/spawning numerous other successful movies and television shows due to its questionable themes, morally ambiguous characters, beautiful cinematography, all-star cast, winning numerous Academy Awards and being widely regarded as one of the best movies of all time. It's 1974 follow-up The Godfather Part II continued the legacy and is generally held to be one of the best sequels of all time as well as having various Sopranos stars co-star in it. It also has Sopranos cast member Tony Lip in his first role as a guest at the Corleone's wedding.
The original movie's main character Vito Corleone (played by Marlon Brando) is parodied by Tony's crew in the Season Two episodes Guy Walks into a Psychiatrist's Office... and Funhouse.