Best comedy movie mistakes of 1971
Continuity mistake: Polly Browne is in her dressing room with a picture of Tony Brockhurst on her mirror. She starts to sing and picks the picture off the mirror. As we see a close-up in her hands it is a totally different picture of Tony. As she puts it back, the photo has reverted back to the original.
Factual error: When Lurcio is dragging his ass through the market he passes several stalls which stock fruits and vegetables totally unknown to the Romans - potatoes, corn, papayas, mangoes and breadfruit amongst them. They were unknown in Europe during the time the film is set, and the Romans did not trade with anyone who knew about them, either.