In which part of Italy does the criminal syndicate Cosa Nostra originate?

Explanation

The Mafia, also known as Costa Nostra, is a secret, Sicilian organisation, said to have emerged in the mid-nineteenth century. The word "mafia" has today become a generic term for any organized criminal network with similar structure, methods, and interests. The word was first used in 1962 in the play "I mafiusi di la Vicaria."