The Sicilian Mafia or Cosa Nostra, also referred to as simply Mafia, is a criminal society and criminal organization originating on the island of Sicily and dates back to the mid-19th century. Emerging as a form of local protection and control over land and agriculture, the Mafia gradually evolved into a powerful criminal network. By the mid-20th century, it had infiltrated politics, construction, and finance, later expanding into drug trafficking, money laundering, and other crimes. At its core, the Mafia engages in protection racketeering, arbitrating disputes between criminals, and organizing and overseeing illegal agreements and transactions.