A group of corrupt officials in New York City, USA. It revolved around William Marcy Tweed (1823–78), the New York city political “boss” and state senator who had built his power through the influence of Tammany Hall. The ring, renowned for corrupt and dishonest dealing and for fraudulent city contracts and extortion, was exposed in the New York Times in 1871. Tweed was arrested and convicted but fled to Spain, from which he was extradited. He died in prison in 1878. The operations of the Tweed Ring were estimated to have cost New York City some $100 million.