Omertà is a Southern Italian code of silence that places importance on silence in the face of questioning by authorities or outsiders; non-cooperation with authorities, the government, or outsiders; and willfully ignoring and generally avoiding interference with the illegal activities of others.

It originated and remains common in Southern Italy, where banditry or brigandage and Mafia-type criminal organizations are strong. Similar codes are also deeply rooted in other areas of the Mediterranean, including rural Spain, Crete (Greece), and Corsica, all of which share a common or similar historic culture with Southern Italy.

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