Italy was represented by 16-year-old Gigliola Cinquetti, with the song '"Non ho l'età", at the 1964 Eurovision Song Contest, which took place on 21 March in Copenhagen. Broadcaster RAI chose the winning song from the 1964 Sanremo Music Festival as their Eurovision entry: the song had been performed twice at Sanremo and Cinquetti was chosen over Patricia Carli as the performer. She would bring Italy its first Eurovision victory in by far the most one-sided contest yet seen.

On the night of the final Cinquetti performed 12th in the running order, following Portugal and preceding Yugoslavia. As with all performances from 1964, only an audio recording of Cinquetti's contest performance is known to survive (although footage of sections of her winning reprise has resurfaced). Audiences in the auditorium at this period were traditionally restrained and respectful, rewarding each performance with the same amount of polite applause. However, the recording captures an unprecedented audience response to a Eurovision song, with loud and sustained cheering alongside thunderous applause. Each national jury awarded 5-3-1 to their top 3 songs, and there was no doubt from the start of the voting that "Non ho l'età" was the winner. Of the other 15 national juries, eight (Austria, Belgium, Finland, Luxembourg, the Netherlands, Portugal, the United Kingdom and Yugoslavia) placed the song first, with three others (Germany, Monaco and Switzerland) ranking it second. At the close of the voting "Non ho l'età" had received 49 points, winning the contest by an enormous margin over runners-up the United Kingdom, who had amassed only 17 points. In terms of points received by the winner in relation to the runner-up, it is the most comprehensive victory in Eurovision history.

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